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Tadalafil 5 mg Alone or in Combination with Tamsulosin 0.4 mg for the Management of Men with Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Prospective Observational Trial

Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

Abstract

Tadalafil 5 mg represents the standard for men with Erectile dysfunction (ED) and lower urinary tract symptoms (LUTS)/benign prostatic enlargement (BPE). We carried out an observational trial aiming to assess the efficacy and safety of Tadalafil compared with Tadalafil plus Tamsulosin. Seventy-five patients complaining of ED and LUTS were treated for 12-weeks with Tadalafil plus placebo (TAD+PLA-group) or with combination therapy tadalafil plus tamsulosin (TAD+TAM-group). Efficacy variables were: International Index of Erectile Function (IIEF), International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax) and safety assessments. Data were evaluated using paired samples T-test (baseline vs. 12-weeks) and analysis of variance (Δgroup-TAD+PLA vs. Δgroup-TAD+TAM). At baseline, both groups presented similar characteristics and symptoms scores (all: p > 0.05). From baseline to 12-weeks, all the subjects showed a significant improvement of IIEF, total-IPSS, storage-IPSS, Qmax (all: p < 0.001). Conversely, a significant improvement of voiding-IPSS was observed in TAD+TAM-group (−3.5 points, p < 0.001). Indeed, TAD+PLA-group showed a not significant improvement of voiding-IPSS (−2.0 points, p = 0.074). When we compared between-groups differences at 12-weeks, IIEF (p = 0.255), total-IPSS (p = 0.084) and storage-IPSS (p = 0.08) did not show any statistically significant differences, whereas, voiding-IPSS and Qmax were significantly better in TAD+TAM-group (p = 0.006 and p = 0.027, respectively). No severe treatment adverse events (TAEs) were reported in both groups. Tadalafil achieved the same improvements of IIEF, total-IPSS, storage-IPSS when compared to combination therapy. Instead, Qmax and voiding-IPSS were better managed with combination therapy, without change of TAEs.

Keywords: benign prostatic hyperplasia, erectile dysfunction, lower urinary tract symptoms, medical therapy, tadalafil, tamsulosin

1. Introduction

Erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) related to benign prostatic obstruction (BPO) are common conditions in middle-age or older men [1]. Men with LUTS have a higher incidence of ED, and LUTS themselves represent an independent risk factor for ED, [2] triggering a significant negative impact on quality of life (QoL). The underlying pathophysiological links between LUTS secondary to benign prostatic hyperplasia (BPH) and ED are not yet completely understood, even though several determinants are shared by these two clinical entities [1,3].

Alpha-blockers (ABs) and 5a-reductase inhibitors (5 ARIs), alone or in combination, are the mostly prescribed drugs to manage patients with LUTS/BPH [4]. ABs are usually the first line treatment for LUTS thanks to their rapid onset of action. By antagonizing alpha(1A)-adrenergic receptors in the prostate and urethra, they cause smooth muscle relaxation in lower urinary tract (LUT) determining the decrease of the functional obstruction [5,6].

The association of AB with 5 ARI has been proposed and widely adopted in order to reduce the overall risk of BPH progression and to improve LUTS in patients with moderate enlarged (≥40 mL) prostates when long term treatment is planned. However, in several sub analysis voiding symptoms and maximum urinary flow rate (Qmax) improvement was not as high as expected. Moreover, these therapies have potential major side-effects on sexual activity, particularly in erectile and ejaculatory function [7,8,9].

Phosphodiesterase type 5 inhibitors (PDE5-Is) were approved for the treatment of ED, but they have been also demonstrated as highly effective in blunting LUTS in men with or without ED [10,11,12,13]. Indeed, PDE5-Is act on the relaxation of bladder neck and prostate by increasing nitric oxide in smooth muscle, allowing a direct action on micturition phases and not only penile erection. [14,15].

Moreover, they exert potent anti-inflammatory effects on prostate therefore reducing fibrosis and overgrowth. All these beneficial effects help in maintaining prostatic structural anatomy and physiological activity [16,17].

Currently the efficacy of PDE5-Is on LUTS recovery has been well established, and tadalafil 5 mg once daily has been approved for the treatment of LUTS/BPH with or without coexisting ED [3].

Recently, a meta-analysis of 12 randomized controlled trials (RCTs) on PDE5-Is suggested that combination therapy with ABs, particularly with tamsulosin, the only AB approved by the Food and Drug Administration in combination with tadalafil for the treatment of LUTS, allows achieving an additional significant improvement of International Prostate Symptom Score (IPSS) as compared to ABs alone. Conversely, we have no definitive evidence for the comparison between PDE5-Is plus ABs vs. PDE5-Is alone [18].

We carried out a prospective placebo-controlled trial, with the aim to compare the efficacy and safety of daily administration tadalafil 5 mg alone (tadalafil plus placebo) with the combination tadalafil 5 mg plus tamsulosin 0.4 mg in men with LUTS/BPH and ED.

2. Materials and Methods

2.1. Study Population and Design

Our prospective observational trial was conducted in two departments of urology. Across a period of 12 months, 82 consecutive men presenting with ED and LUTS suggestive of BPO were enrolled.

Inclusion criteria were: age >40 to 80 years, mild to severe ED (International Index of Erectile Function–Erectile Function-5 <22), moderate to severe LUTS (International Prostate Symptom Score >7) and with Qmax >5 mL/s obtained from a uroflowmetry assessment. Exclusion criteria were: hypersensitivity to tadalafil or tamsulosin, prostatic cancer or suspected with prostate-specific antigen (PSA) >4 ng/mL, bladder lithiasis, previous prostatic surgery, urinary tract infection, neurogenic bladder, finasteride or dutasteride use within 3 or 6 months, respectively, clinical history of urethral and/or proven bladder neck obstruction.

The present trial was carried out according to the ethical principles of the Declaration of Helsinki, following the rules of good clinical practices. The study was approved by the review boards of the two involved institutions (Ethics Committee Approval OSS.15.031, approved on 22 June 2015). All men provided written informed consent before initiating any trial procedure or therapy.

The assessment of patients included age, body mass index (BMI), waist circumference (WC), blood pressure, clinical laboratory parameters, digital rectal examination. LUTS and ED were assessed using validated questionnaires. In particular, LUTS with total International Prostate Symptom Score (IPSS), focusing also on storage and voiding IPSS subscores, nocturia question and IPSS QoL [19], ED with International Index of Erectile Function-5 (IIEF-5) [20]. Uroflowmetry was performed by all the subjects enrolled and postvoid residual volume (PVR) was evaluated with abdominal ultrasound immediately after voiding.

Subjects reporting intake of BPH, overactive bladder, or ED therapies underwent a 4 weeks treatment-free washout period. Moreover, all subjects enrolled underwent a 2 weeks run-in period with tamsulosin 0.4 mg/day alone. Fifty patients enrolled in one center, were treated with tadalafil 5 mg/day plus tamsulosin 0.4 mg/day (TAD+TAM-group) for 12 weeks, otherwise 25 patients enrolled in the other center received tadalafil 5 mg/day plus placebo (TAD+PLA-group). The medications were self-administered every day at the same time, before the night rest, without any limitations or variations of sexual activity timing or food intake. Patients were evaluated at screening, run-in, baseline, and after 12 weeks of treatment ( Figure 1 ).

Disposition of subjects according to Subject Consolidated Standards of Reporting Trials (CONSORT) diagram.

Safety was assessed by evaluating subject-reported adverse events (AEs), orthostatic vital signs, clinical laboratory parameters, uroflowmetry and PVR.

Patients with incomplete data sets were excluded from statistical analysis.

2.2. Statistical Analysis

Differences between tadalafil monotherapy (TAD+PLA-group) and combination therapy (p TAD+TAM-group) were calculated at baseline and 12 weeks, by using the unpaired sample t-test. Instead, the paired sample t-test was adopted to assess mean changes between baseline and week 12 visit in both groups. The one-way analysis of variance (ANOVA) was used to measure the between-group changes from baseline to 12 weeks. All statistical analyses were done with SPSS® (SPSS Inc., Chicago, IL, USA). A p value of 0.05 or less was considered statistically significant.

3. Results

Experimental Results

A Consolidated Standards of Reporting Trials (CONSORT) flow chart is shown in Figure 1 . Of 82 subjects enrolled, 75 were screened. All subjects completed the study. Both groups showed a >90% compliance with dosing requirements.

Mean age was 65 years. No significantly differences in baseline characteristics, including IPSS, and the other BPH-related characteristics (Qmax, symptoms score), were observed between the two groups ( Table 1 ). After 12 weeks of treatment from baseline, total IPSS, storage IPSS, IPSS QoL, IIEF-5 and Qmax statistically significantly improved in both groups (all: p < 0.001) (Table 2 ). Nevertheless, only the subjects in TAD+TAM-group, treated with combination therapy, experienced a statistically and clinically significant recovery of voiding LUTS, with a reduction of −3.5 voiding IPSS points (p < 0.001), when compared with tadalafil monotherapy (−2.0 voiding IPSS points, p = 0.074) ( Table 2 ). No significant differences between TAD+TAM-group and TAD+PLA-group, except for Qmax (p = 0.027) and voiding IPSS (p = 0.006), emerged at between-group ANOVA analysis at week 12 endpoint ( Figure 2 ).

Change from baseline to 12 weeks for tadalafil and tadalafil plus tamsulosin (combination) groups. Graphical representation of the significant differences between the two groups. IPSS = International Prostate Symptom Score.

Table 1

All Patients	TAD + TAM Group n = 50		TAD + PLA Group n = 25		p
Baseline Characteristics	Mean ± SD Deviation	(Minimum-Maximum)	Mean ± SD Deviation	(Minimum-Maximum)	p
Age (years)	65.7 ± 9.1	47–78	65.5 ± 6.3	51–74	0.238
Weight (kg)	78.2 ± 9.2	69–86	75.8 ± 10.4	67–83	0.216
Body mass index (kg/m2)	27 ± 3.1	25–31	26.7 ± 3.6	24–31	0.174
Abdominal obesity: waist circumference (cm)	108.8 ± 4.1	92–135	102.3 ± 5.4	76–120	0.136
Triglycerides (mg/dL)	156.7 ± 8.4	76–247	129.2 ± 7.2	83–185	0.117
HDL cholesterol (mg/dL)	49.4 ± 2.8	31–76	49.8 ± 2.3	32–60	0.259
Glycemia (mg/dL)	111.3 ± 3.5	76–211	102.7 ± 5.7	72–188	0.113
IPSS base	18.8 ± 5.9	8–32	17 ± 6.1	8–29	0.224
IPSS voiding base	8.6 ± 3.8	1–20	10 ± 4.1	3–18	0.146
IPSS storage base	8.3 ± 3.2	0–14	6.9 ± 4.2	1–15	0.118
IPSS QoL base	3.9 ± 1	2–6	3.5 ± 1.4	1–6	0.145
IIEF-5 base	12 ± 3.5	6–21	13.8 ± 5.2	1–21	0.09
Q max base (mL/s)	10.3 ± 3.5	3.4–17.8	9.6 ± 2.8	6–17	0.369

SD = standard deviation; IPSS = International Prostate Symptom Score; IIEF-5 = International Index of Erectile Function-5; Qmax = maximum urinary flow rate.

Table 2

Change from baseline to 12 weeks in tadalafil monotherapy (TAD+PLA-Group) and tadalafil plus tamsulosin (TAD+TAM-Group) groups.

Variables Assesed	TAD + TAM Group n = 50	TAD + PLA Group n = 25	p Value (Anova Analysis)
IPSS 12 week (Mean ± SD)	11.5 ± 5.4	11.8 ± 6.3
Delta3 M (baseline – 12wks)	−7	−5.2
p value (paired samples T-test)			0.084
IPSS voiding 12 week (Mean ± SD)	5.1 ± 2.7	8 ± 4.7
Delta3 M (baseline – 12wks)	−3.5	−2
p value (paired samples T-test)		0.074	0.006
IPSS storage 12 week (Mean ± SD)	5.3 ± 2.7	3.8 ± 3.4
Delta3 M (baseline – 12wks)	−3	−3.1
p value (paired samples T-test)			0.08
IPSS QoL 12 week (Mean ± SD)	2.1 ± 1	2.1 ± 1.7
Delta3 M (baseline – 12wks)	−1.8	−1.3
p value (paired samples T-test)		0.009	0.321
IIEF-5 12 week (Mean ± SD)	17.7 ± 3.3	19.9 ± 5.1
Delta3 M (baseline – 12wks)	5.7	6.1
p value (paired samples T-test)			0.255
Q max 12 week (Mean ± SD)	14.5 ± 3.7	11.8 ± 4
Delta3 M (baseline – 12wks)	4.2	2.2
p value (paired samples T-test)			0.027

p value: significance of the analysis of variance (ANOVA). SD = standard deviation; IPSS = International Prostate Symptom Score; IIEF-5 = International Index of Erectile Function-5; Qmax = maximum urinary flow rate.

The proportion of subjects reporting at least one treatment-emergent AE (TEAE) was 16% in TAD+PLA-group and 22% in TAD+TAM-group ( Table 3 ). TEAEs were mild to moderate in severity. The most common TEAEs in TAD+PLA-group were headache (n = 2) followed by back pain (n = 1) and nasopharyngitis (n = 1), whereas the most common TEAEs with combination therapy (TAD+TAM) were headache (n = 4), back pain (n = 3), ejaculatory dysfunction (semen volume decreased/retrograde ejaculation) (n = 2), dyspepsia (n = 1) and dizziness (n = 1). Laboratory measurements or vital signs did not show any clinically significant changes. No episodes of urinary retention were reported. No subject discontinued therapy because of TEAEs.

Table 3

Summary of adverse events at treatment period (12 weeks).

Adverse Events	TAD + TAM Group n = 50, (n %)	TAD + PLA Group n = 25, (n %)	p Value
Any TEAEs	11 (22%)	4 (16%)	0.075
Serious AEs	0 (0%)	0 (0%)	0.267
Intensity
mild	7 (14%)	3 (12%)	0.114
moderate	4 (8%)	1 (4%)	0.098
severe	0 (0%)	0 (0%)	0.286
Headache	4 (8%)	2 (8%)	0.163
Nasopharyngitis	0 (0%)	1 (4%)	0.196
Back pain	3 (6%)	1(4%)	0.087
Dizziness	1 (2%)	0 (0%)	0.173
Dyspepsia	1 (2%)	0 (0%)	0.185
Ejaculatory dysfunction	2 (4%)	0 (0%)	0.072

AEs = adverse events. TEAEs = treatment-emergent adverse events.

4. Discussion

In this study, we found that daily administration of tadalafil 5 mg was effective in improving the overall urinary symptoms, without any difference between monotherapy or combination with tamsulosin 0.4 mg, but also uroflowmetry parameters. Nevertheless, men treated with combination therapy showed a more remarkable improvement of Qmax and voiding IPSS compared with tadalafil alone.

In elderly men ED and LUTS related to benign prostatic enlargement (BPE) represent a high prevalence comorbid condition with a negative impact on patients’ QoL and significant economic burden. It has been established in preclinical and clinical trials that besides aging, several metabolic factors affect the onset and worsening of both ED and LUTS, concurring to penile and nerves alterations and also prostate enlargement and inflammation [21]. Even if the pathophysiological pathways shared between ED and LUTS are still not totally elucidated, PDE5-Is proved to be effective for the treatment of both these conditions [1,14].

Indeed, PDE5-Is are able to manage prostate inflammation and could act on the related fibrosis by improving pelvic and prostate oxygenation. Moreover, it seems that they might contribute to restore the physiologic activity of prostate and to stabilize the glandular structural anatomy [17,22,23].

Other relevant PDE5-Is’ mechanisms of action are emerging and are currently under investigation. There is a significant body of evidence supporting the relaxating action of PDE5-Is on the smooth muscle fibers of bladder neck, urethra, and prostate. Furtehrmore, even if with less effectiveness, they might reduce the tone of bladder muscles and affect the micturition reflex, by improving LUT blood supply and modulating bladder afferent innervation [14].

Several RCTs demonstrated that PDE5-Is are able to significantly decrease IPSS score, ameliorating both storage and voiding LUTS, and improve patients’ QoL. However, in most trials, Qmax was not significantly different from placebo [10,24,25,26].

Likewise, in a meta-analysis by Gacci et al., IPSS and IIEF scores, but not Qmax, were significantly improved by PDE5-Is, [14,27] as in the first systematic review about the use of PDE5-Is for LUTS associated with BPE, Laydner et al. reported that PDE5-Is improve IPSS score and IIEF-5 but not Qmax [28]. However, in a recent study by Roehrborn et al. evaluating the efficacy of tadalafil 5 mg once daily, a slight but significant Qmax increase was observed [26].

Moreover, in a subset analysis based on data from a systematic review, daily administration of tadalafil 5 mg was associated with a remarkable improvement of both ED and LUTS/BPH. [29]. Thus, according to EAU guidelines, tadalafil 5 mg is presently considered a valuable treatment option also for men with moderate to severe LUTS suggestive of BPE [4].

In clinical practice, tadalafil once daily is increasingly prescribed as first-line therapy for LUTS/BPE and concomitant ED. However, several patients, in particular those with prevalent voiding LUTS, often switch to other medical treatments, rarely considering an ongoing tadalafil/tamsulosin combination therapy, even if combination therapy has been proposed by several authors [30,31].

From our results, both subjective and objective parameters were significantly improved at the end of the trial in the 2 treatment arms, supporting the evidence for the use of tadalafil 5 mg as monotherapy or in combination with tamsulosin 0.4 mg in men with ED and LUTS. In particular, we observed a clinically meaningful recovery of LUTS, since a decrease ≥25% or ≥3 points of total IPSS was achieved in both groups. However, at the end of the trial, Qmax and voiding IPSS were significantly better in men treated with combination therapy compared to tadalafil only. Indeed, tadalafil 5 mg significantly decreased total IPSS of >30% and improved Qmax after 12 weeks of monotherapy (mean improvement of Qmax: +2.24 mL/s). Nevertheless, higher improvements in voiding symptoms were observed with combination of tadalafil and tamsulosin.

The results from the first meta-analysis on PDE5-Is for the treatment of ED and LUTS, proved the improvement of IPSS score and Qmax, besides ED evaluated with IIEF score, in men treated with the association of ABs and PDE5-Is compared to ABs alone. [18]. Our data support and enhance the foundings of a recent meta-analysis by Yan et al. Indeed, compared with the use of PDE5-Is alone, the combined therapy of PDE5-Is plus ABs allowed achieving a significant improvement of sexual activity (+2.25 mean difference of IIEF) and LUTS (−4.21 of IPSS), (+1.43 in Qmax) [32].

Accordingly, the results of our study suggest that adding tamsulosin to tadalafil allows to achieve a further improvement of Qmax and voiding symptoms as compared to tadalafil monotherapy after 12 weeks of therapy. However, the similar overall improvement of LUTS (total IPSS and IPSS QoL) and ED (IIEF-5) between the 2 treatment arms, may theoretically allow a increasingly patient-oriented personalized therapy.

Concerning Qmax, McVary et al. demonstrated in two 12 weeks randomized studies comparing tadalafil or sildenafil with placebo, a nearly double improvement of Qmax in subjects treated with PDE5-Is. [10,33].

Anyway, as reported by Tuncel et al., the improvement of Qmax was significantly better in patient treated with combination therapy (+42%) of sildenafil and tamsulosin, compared with the two drugs alone [34].

Similar findings have been showed by Kaplan et al. in a randomized trial comparing alfuzosin with sildenafil or the combination of both. After 12 weeks the improvement of Qmax was 21% for combination therapy, 6% for sildenafil and 11% for alfuzosin [35].

Our results, in agreement with the previous studies, [10,33,34,35] proved that voiding LUTS and uroflowmetric parameters could be significantly further improved with the addition ABs to PDE5 I therapy. Thus, based on prevailing LUTS reported at first or at follow-up visit, a more precise patients’ counselling and medications might be offered in daily clinical practice, according to our findings. Tadalafil 5 mg daily dose was well tolerated both in monotherapy or in combination with tamsulosin 0.4 mg.

Even if the occurrence of AEs was slightly higher in combination therapy group (22% vs. 16%), none of them was severe and we did not observe any withdrawal from the trial due to AEs. Conversely Bechara et al. reported a 1/15 discontinuation in the group treated with tadalafil plus tamsulosin [36] and Chung et al. 4/82 discontinuations [37] with tamsulosin associated with udenafil. Headache was the main AE reported, and the same incidence in both groups (8%) was found. Moreover, in line with previous data, the co-administration of tadalafil and tamsulosin was not associated with symptomatic hypotension [38].

The strengths of the present study are the well sized and homogenous population, the prospective organization of the trial and the data collection. However, this study may be restricted by several limitations. Because this study was observational, it could be prone to biases. Moreover, we did not consider prostate size as inclusion or exclusion criterion or as a possible factor influencing the effectiveness of treatments evaluated. A long-term follow-up is also needed.

5. Conclusions

Tadalafil 5 mg daily monotherapy is able to improve ED and overall LUTS (IPSS and Qmax) after 12 weeks. However, the addition of tamsulosin 0.4 mg to tadalafil 5 mg can further enhance the improvement of voiding symptoms and Qmax. Combination therapy is well tolerated. Even if the overall occurrence of ds is slightly higher as compared with tadalafil alone, their low severity allows achieving good compliance and safety.

Further studies, with longer follow-ups, are still required to assess long term efficacy and safety of tadalafil and tamsulosin coadministration.

Author Contributions

Data curation, J.F.; Formal analysis, M.S.; Project administration, M.G.; Resources, O.S.; Supervision, A.T., M.M. and S.S.; Validation, C.D.N. and L.V.; Visualization, K.T.M., S.A.K., S.G. and C.C.; Writing—original draft, P.S.; Writing—review & editing, A.S.

Conflicts of Interest

The authors declare no conflict of interest.

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Articles from Journal of Clinical Medicine are provided here courtesy of Multidisciplinary Digital Publishing Institute (MDPI)

Tamsulosin (Flomax) interactions: what you need to know

If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

Tamsulosin (brand name Flomax) is a medication used to treat benign prostatic hyperplasia (BPH). As with many medications, potential drug interactions may occur with tamsulosin. It’s important to tell your healthcare provider about all medications (both prescription and nonprescription), supplements, and herbal products you’re taking before beginning a new medication.

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Connect with a US-licensed healthcare provider about ED, premature ejaculation, hair loss, and more.

What is tamsulosin?

Tamsulosin (brand name Flomax) is an alpha-blocker that’s FDA-approved to treat the urinary symptoms of BPH, also referred to as an enlarged prostate. You can only get it with a prescription, but it is available as either generic tamsulosin or brand name Flomax.

Tamsulosin drug interactions

Sildenafil and other PDE5 inhibitors

Phosphodiesterase-5 (PDE5) inhibitors are oral medications used to treat erectile dysfunction (ED). They work by dilating blood vessels to allow more blood flow into the penis, improving your erection. However, dilating blood vessels also lowers blood pressure. Taking both tamsulosin and PDE5 inhibitors may low blood pressure, also called hypotension (DailyMed, 2017). Examples of PDE5 inhibitors include sildenafil (brand name Viagra; see Important Safety Information), tadalafil (brand name Cialis; see Important Safety Information), vardenafil (brand name Levitra), and avanafil (brand name Stendra). Ask your healthcare provider if it’s safe to take a PDE5 inhibitor while taking tamsulosin.

CYP3A4 and CYP2D6 blockers

CYP3A4 and CYP2D6 are two enzymes in the liver that break down tamsulosin. Any drug that blocks or inhibits CYP3A4 and CYP2D6 can increase the concentration of tamsulosin in the body. This can increase the likelihood of developing adverse effects, like hypotension and syncope (fainting) (DailyMed, 2017). In some cases, your healthcare provider may adjust your medication dose. Examples of these drugs include cimetidine, ketoconazole, erythromycin, terbinafine, and paroxetine.

Blood pressure medications

Since tamsulosin may lower your blood pressure, you should be careful while being treated for high blood pressure. If you’re already taking medication for high blood pressure (hypertension), ask your healthcare provider if it’s safe for you to take tamsulosin as well. Taking tamsulosin along with blood pressure medications can increase the risk of orthostatic hypotension (OH), which is dizziness or fainting upon standing; these symptoms are due to a sudden drop in blood pressure (Biaggioni, 2018).

BPH treatment: when is it needed and what’s available?

Tamsulosin uses

Tamsulosin is FDA-approved to relieve symptoms of benign prostatic hyperplasia (BPH), otherwise known as an enlarged prostate (DailyMed, 2017). As men get older, their prostates naturally get larger. In some men, this can put pressure on the urethra and bladder, partially obstructing the flow of urine. This can cause symptoms like:

Increased need to urinate, particularly at night
Difficulty urinating (straining, frequent starting and stopping)
Weak urine stream
Trouble beginning urination

Tamsulosin causes smooth muscles in the prostate and bladder to relax, making urination easier.

Tamsulosin is also prescribed “off-label” for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and kidney stones that have moved into the urethra (UpToDate, n.d.). By causing smooth muscles in the area to relax, tamsulosin can help dislodge those stones, allowing them to be passed naturally in the urine stream.

Tamsulosin drug class

Tamsulosin (or tamsulosin hydrochloride) is part of a class of drugs called alpha blockers, also called selective alpha-1a adrenergic receptor antagonists (NIDDK, 2018). Tamsulosin targets receptors in the smooth muscles of the prostate and bladder, causing them to relax, thereby improving symptoms.

Other examples of alpha blockers include alfuzosin (brand name Uroxatral), doxazosin (brand name Cardura), silodosin (brand name Rapaflo), and terazosin (brand name Hytrin).

Generic Flomax for enlarged prostate

Tamsulosin side effects

Like many medications, tamsulosin can cause side effects. These can range from mild to serious.

Common side effects of tamsulosin include:

Headache
Dizziness
Abnormal ejaculation
Runny nose or nasal congestion
Drowsiness
Back pain
Stomach upset, diarrhea, and nausea

Less common side effects of tamsulosin include

Orthostatic hypotension, which is dizziness, lightheadedness, or fainting (syncope) when moving from a sitting to standing position. It’s caused by a sudden drop in blood pressure.
Chest pain
Loss of libido
Intraoperative floppy iris syndrome (IFIS) which can occur during glaucoma surgery or cataract surgery.
Priapism, a painful erection that lasts more than four hours

Some people who are allergic to sulfonamides, or sulfa drugs, may also have an allergic reaction to tamsulosin. Allergic reactions may include a skin rash, swelling, or trouble breathing.

This is not a complete list of side effects. Seek medical advice from your healthcare professional or pharmacist if you have questions about tamsulosin side effects or drug interactions.

References

American Urology Association (AUA). (2020). Urology Care Foundation: What is benign prostatic hyperplasia?. Retrieved on Sep. 8, 2020 from https://www.urologyhealth.org/urologic-conditions/benign-prostatic-hyperplasia-(bph)
Biaggioni, I. (2018). Orthostatic Hypotension in the Hypertensive Patient. American Journal of Hypertension, 31(12), 1255–1259. https://doi.org/10.1093/ajh/hpy089. Retrieved from https://academic.oup.com/ajh/article/31/12/1255/5047643
DailyMed. (n.d.). FLOMAX- tamsulosin hydrochloride capsule. Retrieved Sep. 10, 2020 from https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c00d5f7b-dad7-4479-aae2-fea7c0db40ed
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). (2018). Alpha 1 Adrenergic Receptor Antagonists. In LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. Retrieved from https://pubmed.ncbi.nlm.nih.gov/31644028/
UpToDate. (n.d.). Tamsulosin: Drug information. Retrieved on Sep. 8, 2020 from https://www.uptodate.com/contents/tamsulosin-drug-informatio

Tamsulosin dosage: what’s right for me?

Tamsulosin (Flomax) warnings: be aware of these issues

Tamsulosin (Flomax): everything you need to know

Drugs that cause erectile dysfunction: what to do when your medication has sexual side effects

Avanafil (Stendra): uses, side effects, interactions, and more

Finasteride interactions: what you need to know

Generic Flomax for enlarged prostate

BPH treatment: when is it needed and what’s available?

Important Safety Information for Sildenafil (Viagra)

What are the most important things I need to know about VIAGRA® (sildenafil citrate) 25 mg, 50 mg, and 100 mg tablets and generic VIAGRA®?

Discuss your health with your doctor to ensure that you are healthy enough for sex. If you experience chest pain, dizziness, or nausea during sex, seek immediate emergency medical attention.

VIAGRA® and generic VIAGRA® can cause serious side effects. Serious, but rare, side effects include:

an erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, seek emergency medical attention right away. If it is not treated right away, priapism can permanently damage your penis.
sudden vision loss in one or both eyes. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION). Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss
sudden hearing decrease or hearing loss. Some people may also have ringing in their ears (tinnitus) or dizziness. If you have these symptoms, stop taking VIAGRA and contact a doctor right away

Who should not take VIAGRA® or generic VIAGRA®?

Do not take VIAGRA® or generic VIAGRA® if you:

Take any medicines called nitrates, often prescribed for chest pain, or guanylate cyclase stimulators like Adempas (riociguat) for pulmonary hypertension. Your blood pressure could drop to an unsafe level
Are allergic to sildenafil, as contained in VIAGRA® and REVATIO®, or any of the ingredients in VIAGRA® or generic VIAGRA® tablets.
Are a women or a child

When should I call my primary provider?

Call your primary provider right away if you:

Have an erection that lasts longer than 4 hours
Experience a sudden loss of vision in one or both eyes
Experience a sudden decrease in or loss of hearing
Experience chest pain, dizziness, or nausea during sex
Take too much Viagra or sildenafil citrate

If you are experiencing a medical emergency, call 911 or seek immediate medical attention.

What are the most common side effects of VIAGRA® and generic VIAGRA®?

headache
flushing
upset stomach
abnormal vision, such as changes in color vision (such as having a blue color tinge) and blurred vision
stuffy or runny nose
back pain
muscle pain
nausea
dizziness
rash

What should I tell my Roman-affiliated provider before taking VIAGRA® and generic VIAGRA®?

Before you take VIAGRA® or generic VIAGRA® , tell your healthcare provider if you:

Have or have had heart problems such as a heart attack,irregular heartbeat, angina, chest pain, narrowing of the aortic valve, or heart failure
Have had heart surgery within the last 6 months
Have pulmonary hypertension
Have had a stroke
Have low blood pressure, or high blood pressure that is not controlled
Have a deformed penis shape
Have had an erection that lasted for more than 4 hours
Have problems with your blood cells such as sickle cell anemia, multiple myeloma, or leukemia
Have retinitis pigmentosa, a rare genetic (runs in families) eye disease
Have ever had severe vision loss, including an eye problem called NAION
Have bleeding problems
Have or have had stomach or intestinal ulcers
Have liver problems
Have kidney problems or are having kidney dialysis
Have any other medical conditions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

VIAGRA may affect the way other medicines work, and other medicines may affect the way VIAGRA works, causing side effects.

Especially tell your healthcare provider if you take any of the following:

Medicines called nitrates
Medicines called guanylate cyclase stimulators such as Adempas® (riociguat)
Medicines called alpha-blockers such as Hytrin® (terazosin HCl), Flomax® (tamsulosin HCl), Cardura® (doxazosin mesylate), Minipress® (prazosin HCl), Uroxatral® (alfuzosin HCl), Jalyn® (dutasteride and tamsulosin HCl), or Rapaflo® (silodosin). Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. In some patients, the use of VIAGRA® with alpha-blockers can lead to a drop in blood pressure or to fainting
Medicines called HIV protease inhibitors, such as ritonavir (Norvir®), indinavir sulfate (Crixivan®), saquinavir (Fortovase® or Invirase®), or atazanavir sulfate (Reyataz®)
Oral antifungal medicines, such as ketoconazole (Nizoral®) and itraconazole (Sporanox®)
Antibiotics, such as clarithromycin (Biaxin®), telithromycin (Ketek®), or erythromycin
Other medicines that treat high blood pressure
Other medicines or treatments for ED
VIAGRA® contains sildenafil, which is the same medicine found in another drug called REVATIO®. REVATIO® is used to treat a rare disease called pulmonary arterial hypertension (PAH). VIAGRA® should not be used with REVATIO® or with other PAH treatments containing sildenafil or any other PDE5 inhibitors (such as Adcirca [tadalafil])

Withholding or providing inaccurate information about your health and medical history in order to obtain treatment may result in harm, including, in some cases, death.

What is the FDA-approved use of VIAGRA® and generic VIAGRA®?

VIAGRA® (sildenafil citrate) is prescription medicine used to treat erectile dysfunction (ED).

Roman-affiliated doctors may prescribe VIAGRA® or generic VIAGRA® for the treatment of premature ejaculation (PE), if they believe in their medical judgment that it is an appropriate course of treatment. While this is not an FDA-approved use of the drug, the American Urological Association has included the use of sildenafil citrate in the treatment of PE in its Guideline on the Pharmacologic Management of Premature Ejaculation.

You are encouraged to report negative side effects of prescription products to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

Please see the full Prescribing Information for complete safety information.

Product names referenced herein are trademarks of their respective owners.

Important Safety Information for Tadalafil (Cialis)

What Is The Most Important Information I Should Know About CIALIS® (tadalafil) and generic CIALIS®?

CIALIS® and generic CIALIS® can cause serious side effects. Serious, but rare, side effects include:

An erection that won’t go away (priapism). If you get an erection that lasts more than 4 hours, get medical help right away. Priapism must be treated as soon as possible or lasting damage can happen to your penis, including the inability to have erections.
Changes in vision. Color vision changes, such as seeing a blue tinge (shade) to objects or having difficulty telling the difference between the colors blue and green.
Sudden decrease or loss of vision. In rare instances, men taking PDE5 inhibitors (oral erectile dysfunction medicines, including CIALIS® and generic CIALIS®) reported a sudden decrease or loss of vision in one or both eyes. It is uncertain whether PDE5 inhibitors directly cause the vision loss. If you experience sudden decrease or loss of vision, stop taking PDE5 inhibitors, including CIALIS® and generic CIALIS®, and call a healthcare provider right away.
Sudden loss or decrease in hearing. Sudden loss or decrease in hearing, sometimes with ringing in the ears and dizziness, has been rarely reported in people taking PDE5 inhibitors, including CIALIS® and generic CIALIS®. It is not possible to determine whether these events are related directly to the PDE5 inhibitors, to other diseases or medications, to other factors, or to a combination of factors. If you experience these symptoms, stop taking CIALIS® and generic CIALIS® and contact a healthcare provider right away.
ED is a condition where the penis does not fill with enough blood to harden and expand when a man is sexually excited, or when he cannot keep an erection. A man who has trouble getting or keeping an erection should see his healthcare provider for help if the condition bothers him.
CIALIS® and generic CIALIS® help increase blood flow to the penis and may help men with ED get and keep an erection satisfactory for sexual activity. Once a man has completed sexual activity, blood flow to his penis decreases, and his erection goes away. Some form of sexual stimulation is needed for an erection to happen with CIALIS® or generic CIALIS®.

CIALIS® and generic CIALIS® do not:

Cure ED
Increase a man’s sexual desire
Protect a man or his partner from sexually transmitted diseases, including HIV. Speak to your healthcare provider about ways to guard against sexually transmitted diseases.
Serve as a male form of birth control

Take CIALIS® or generic CIALIS® exactly as your healthcare provider prescribes it. Your healthcare provider will prescribe the dose that is right for you. Do not change your dose or the way you take CIALIS® or generic CIALIS® without talking to your healthcare provider.

Who Should Not Take CIALIS® or generic CIALIS®?

Do not take CIALIS® or generic CIALIS® if you:

Have severe liver disease. Tell your doctor if you have mild to moderate liver disease as you may need dosage reductions.
Have severe kidney disease. Tell your doctor if you have mild to moderate kidney disease as you may need dosage reductions
Take any medicines called “nitrates”
Use recreational drugs called “poppers” like amyl nitrite and butyl nitrite
Take any medicines called guanylate cyclase stimulators, such as riociguat
Are allergic to CIALIS®, tadalafil or ADCIRCA®, or any of its ingredients

When should I call my primary provider?

Call your primary provider right away if you:

Have an erection that lasts longer than 4 hours
Experience a sudden loss of vision in one or both of your eyes
Experience a sudden decrease or loss hearing
Take too much CIALIS® or generic CIALIS®
Have an allergic reaction to CIALIS® or generic CIALIS®
Symptoms of an allergic reaction may include:
Rash
Hives
Swelling of the lips, tongue, or throat
Difficulty breathing or swallowing

Call your healthcare provider or get help right away if you have any of the symptoms of an allergic reaction listed above.

If you are experiencing a medical emergency, call 911 or seek immediate medical attention.

What Should I Tell My Roman-affiliated Provider Before Taking CIALIS® and generic CIALIS®?

Tell your Roman-affiliated provider about all your medical problems, including if you:

Have heart problems such as angina, heart failure, irregular heartbeats, or have had a heart attack. Ask your healthcare provider if it is safe for you to have sexual activity. You should not take CIALIS® and generic CIALIS® if your healthcare provider has told you not to have sexual activity because of your health problems.
Have pulmonary hypertension
Have low blood pressure or have high blood pressure that is not controlled
Have had a stroke
Have liver problems
Have kidney problems or require dialysis
Have retinitis pigmentosa, a rare genetic (runs in families) eye disease
Have ever had severe vision loss, including a condition called NAION
Have stomach or intestinal ulcers
Have a bleeding problem
Have a deformed penis shape or Peyronie’s disease
Have had an erection that lasted more than 4 hours
Have blood cell problems such as sickle cell anemia, multiple myeloma, or leukemia

Tell your healthcare provider about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Especially tell your healthcare provider if you take any of the following:

Medicines called nitrates
Medicines called guanylate cyclase stimulators, such as riociguat (Adempas®), used to treat pulmonary hypertension
Medicines called alpha blockers. These include Hytrin® (terazosin HCl), Flomax® (tamsulosin HCl), Cardura® (doxazosin mesylate), Minipress® (prazosin HCl), Uroxatral® (alfuzosin HCl), 4 Jalyn® (dutasteride and tamsulosin HCl) or Rapaflo® (silodosin). Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. If CIALIS® or generic CIALIS® is taken with certain alpha blockers, your blood pressure could suddenly drop. You could get dizzy or faint.
Other medicines to treat high blood pressure (hypertension)
Medicines called HIV protease inhibitors, such as ritonavir (Norvir® , Kaletra® )
Oral antifungals such as ketoconazole (Nizoral® ), itraconazole (Sporanox® )
Antibiotics such as clarithromycin (Biaxin® ), telithromycin (Ketek® ), erythromycin (several brand names exist. Please consult your healthcare provider to determine if you are taking this medicine).
Other medicines or treatments for ED.
Tadalafil is also marketed as ADCIRCA® for the treatment of pulmonary arterial hypertension. Do not take both CIALIS® or generic CIALIS® and ADCIRCA®. Do not take sildenafil citrate (Revatio®, Viagra®) with CIALIS® or generic CIALIS®.

Withholding or providing inaccurate information about your health and medical history in order to obtain treatment may result in harm, including, in some cases, death.

What are the most common side effects of CIALIS® or generic CIALIS®?

The most common side effects with CIALIS® and generic CIALIS® are:

What is the FDA-approved Use of CIALIS® and generic CIALIS®?

CIALIS® and generic CIALIS® are prescription medicines used to treat erectile dysfunction (ED), symptoms of benign prostatic hyperplasia (BPH), or both.

Roman-affiliated doctors may prescribe CIALIS® for the treatment of premature ejaculation (PE), if they believe in their medical judgment that it is an appropriate course of treatment.

You are encouraged to report negative side effects of prescription products to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

Please see the full Prescribing Information for complete safety information.

Combining flomax and cialis can effectively treat urinary symptoms as well as erectile dysfunction

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In a nutshell

This study examined whether combining tadalafil (Cialis) and tamsulosin (Flomax) can reduce both urinary symptoms as well as erectile dysfunction. This treatment combination was safe and effective in reducing urinary symptoms and improving erectile function.

Some background

Many men with benign prostatic hyperplasia (BPH) experience both urinary symptoms as well as erectile dysfunction. One report found that 72.2% of men with urinary symptoms due to BPH also had erectile dysfunction. Only 37.7% had urinary symptoms without some form of erectile dysfunction.

Tamsulosin is a type of alpha-blocker commonly prescribed for urinary symptoms. It works by relaxing the muscles in the prostate and bladder neck, making it easier to urinate. Tadalafil is a type of phosphodiesterase-5 inhibitor developed for erectile dysfunction. It increases blood flow to the penis and it also helps to relax muscle cells in the bladder and prostate. Both tamsulosin alone and tadalafil alone are commonly used to treat each condition separately. Whether they are safe and effective when combined is still under investigation.

Methods & findings

This study included 510 men with BPH. All men reported urinary symptoms as well as erectile dysfunction. Men were randomly assigned to treatment groups. 153 men were treated with high-dose tamsulosin (0.4 mg) plus tadalafil (5 mg). 164 men were treated with low-dose tamsulosin (0.2 mg) plus tadalafil (5 mg). 162 men were treated with tadalafil alone (5 mg). Treatment outcomes were compared between groups at 12 weeks.

Men treated with the 0.4/5 mg combination showed significantly better improvements in urinary symptoms compared to men treated with tadalafil alone. Both groups improved erectile function. The change in urinary symptoms among men treated with the 0.2/5 mg combination was not superior when compared to tadalafil alone.

No significant difference in the rate of side effects was observed between groups. 14.11% of men treated with the 0.4/5 mg combination reported side effects. It was 8.43% among men treated with the 0.2/5 mg combination and 5.85% in the group receiving tadalafil alone. Common side effects included headache, nasal congestion, and flushing. Only 0.6 and 1.8% of men reported serious side effects.

The bottom line

This study concluded that the combination of 0.4 mg of tamsulosin and 5 mg of tadalafil reduced urinary symptoms as well as erectile dysfunction safely and effectively in men with BPH.

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Cialis interactions: Alcohol, medications, and other factors

Cialis (tadalafil) is a brand-name prescription drug used in males* to treat erectile dysfunction and symptoms of benign prostatic hyperplasia.

As with other medications, Cialis can interact with certain other drugs, foods, and alcohol. An interaction occurs when one substance causes another substance to have a different effect than expected.

For details about Cialis’s interactions, keep reading. For additional information about Cialis, see this article.

* Sex and gender exist on spectrums. Use of the term “male” in this article refers to sex assigned at birth.

In some cases, a factor or condition could prevent your doctor from prescribing Cialis due to the risk of harm. This is known as a contraindication. The contraindications of Cialis include:

Taking a guanylate cyclase stimulator

Doctors are not likely to prescribe Cialis with guanylate cyclase (GC) stimulators. These medications are used to treat pulmonary arterial hypertension. (This is a form of high blood pressure in the arteries of the lungs.)

Both Cialis and GC stimulators may lower blood pressure. Taking Cialis in combination with a GC stimulator could lower your blood pressure further.

Examples of GC stimulators that can interact with Cialis include vericiguat (Verquvo) and riociguat (Adempas).

If you’re taking a GC stimulator, talk with your doctor before taking Cialis. They can recommend a treatment other than Cialis for your condition.

Taking a nitrate

Doctors are not likely to prescribe Cialis with nitrates. These medications are used to help prevent or treat angina (a type of chest pain).

Both Cialis and nitrates can lower blood pressure. Taking Cialis in combination with a nitrate may lower blood pressure further. A sudden drop in blood pressure can lead to fainting and dizziness. In severe cases, it may lead to heart attack or stroke.

Examples of nitrates that can interact with Cialis include:

In addition to the medications above, nitrates also include a group of drugs called poppers. An example of a popper is amyl nitrate.

If you’re taking a nitrate, talk with your doctor before taking Cialis. They can advise you on treatments other than Cialis for your condition.

Having had an allergic reaction to Cialis or any of its ingredients

If you have had an allergic reaction to Cialis or any of its ingredients, your doctor will likely not prescribe Cialis. Taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices.

Note: Before you start treatment with Cialis, it’s important to tell your doctor if any of these contraindications apply to you. They can determine whether to prescribe Cialis.

Doctors may recommend limiting the amount of alcohol you consume while taking Cialis. This is because both alcohol and Cialis can lower blood pressure. Drinking alcohol during Cialis treatment could lower blood pressure further.

If you drink alcohol, talk with your doctor before taking Cialis. They can recommend an amount, if any, that’s safe to consume during your treatment.

Before you start treatment with Cialis, tell your doctor and pharmacist which prescription, over-the-counter, and other medications you take. By sharing this information with them, you may help prevent possible interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Here’s a chart of drugs that can interact with Cialis. Due to the risk of interactions, doctors may not prescribe Cialis with these medications. Keep in mind that this chart does not include all drugs that may interact with Cialis. Some of these interactions are described in detail just below in “Drug interactions in depth.”

Drug class or drug name	Drug examples	Interaction result with Cialis
guanylate cyclase (GC) stimulators*	• vericiguat (Verquvo) • riociguat (Adempas)	can increase the effect of GC stimulators
nitrates*	• isosorbide dinitrate (Isordil) • isosorbide mononitrate (Monoket) • nitroglycerin (Nitro-Dur, NitroMist, Nitrostat)	can increase the effect of nitrates
alpha-blockers	• tamsulosin (Flomax) • terazosin • alfuzosin (Uroxatral)	can increase the effect of alpha-blockers
blood pressure drugs	• angiotensin receptor blockers, such as losartan (Cozaar) • angiotensin converting enzyme inhibitors, such as enalapril (Epaned, Vasotec) • calcium channel blockers, such as amlodipine (Norliqva, Norvasc) • beta-blockers, such as metoprolol (Lopressor, Toprol XL)	can increase the effect of blood pressure drugs
PDE5 inhibitors	• avanafil (Stendra) • vardenafil (Staxyn) • sildenafil (Viagra, Revatio) • other forms of tadalafil (Adcirca, Alyq)	can increase the risk of side effects from Cialis†
certain protease inhibitors	• ritonavir (Norvir) • atazanavir (Reyataz) • darunavir (Prezista)	can increase the risk of side effects from Cialis†
certain antifungal drugs	• itraconazole (Sporanox, Tolsura) • levoketoconazole (Recorlev) • ketoconazole • voriconazole (Vfend)	can increase the risk of side effects from Cialis†
certain antibiotic drugs	• clarithromycin • erythromycin (E.E.S., EryPed, Ery-Tab, others) • rifampin (Rifadin, Rimactane)	can increase the risk of side effects from Cialis†
certain antiseizure drugs	• carbamazepine (Carbatrol, Epitol, Tegretol, others) • phenobarbital • phenytoin (Dilantin, Phenytek)	can make Cialis less effective than usual

* For details about this interaction, see “When to avoid Cialis” above.
† To learn about possible side effects of Cialis, see this article.

Here’s a closer look at certain drug interactions of Cialis.

PDE5 inhibitors

Interaction result. Taking a PDE5 inhibitor with Cialis can increase the risk of low blood pressure.

Interaction explained. Cialis belongs to a class of drugs called PDE5 inhibitors. Medications in this class, including Cialis, can lower blood pressure. Taking Cialis with other drugs in the same drug class can increase the risk of low blood pressure further.

Examples of PDE5 inhibitors. PDE5 inhibitors that may interact with Cialis include the following:

Steps you or your doctor may take. Due to this risk, doctors typically will not prescribe Cialis in combination with other PDE5 inhibitors. Before taking Cialis, it’s important to tell your doctor if you’re already taking a PDE5 inhibitor. They’ll likely prescribe a treatment other than Cialis for your condition.

Certain antibiotic drugs

Antibiotic drugs are used to treat infections caused by bacteria.

Interaction result. Taking Cialis with certain antibiotics can increase the risk of side effects of Cialis. (To learn more about the side effects of Cialis, see this article.)

Interaction explained. Certain antibiotics can prevent your body from breaking down Cialis. This can result in a higher level of the drug in your body than usual. A high level of the drug in your system could increase risk of side effects from Cialis.

Examples of antibiotic drugs. Below are a few antibiotics that may interact with Cialis:

Steps you or your doctor may take. If you’re taking an antibiotic, talk with your doctor before starting Cialis treatment. They can advise you on whether it’s safe for you to take Cialis with these medications.

Certain antiseizure drugs

Interaction result. Taking Cialis with certain antiseizure drugs can make Cialis less effective than usual.

Interaction explained. Certain antiseizure drugs may cause your body to break down Cialis more quickly than usual. This could result in a lower level of the drug in your body than usual, which could make the drug less effective for treating your condition.

Examples of antiseizure drugs. Antiseizure drugs that may interact with Cialis include those listed below:

Steps you or your doctor may take. Before taking Cialis, tell your doctor if you’re taking antiseizure drugs. They can advise you on whether these medications may interact with Cialis.

Cialis may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below.

Cialis and supplements

It’s possible for drugs to interact with supplements such as vitamins and herbs.

Cialis and herbs

Taking Cialis with an herb called St. John’s wort can decrease how well Cialis works. The herb is sometimes used to treat depression.

Be sure to talk with your doctor about taking both St. John’s wort and Cialis. Your doctor may be able to provide you with alternative treatment options.

Cialis and vitamins

No vitamin interactions have been reported with Cialis. You should still check with your doctor or pharmacist before taking any vitamins during Cialis treatment.

Cialis interactions with food

Drinking grapefruit juice or eating grapefruit while taking Cialis could raise the level of Cialis in your body. A higher level of the drug could increase your risk of side effects. (To learn about possible side effects of Cialis, see this article.)

If you have questions about taking Cialis with other foods or drinks, such as coffee, talk with your doctor or pharmacist.

Cialis and vaccines

Vaccines have not been reported to interact with Cialis. If you have questions about getting certain vaccines during your Cialis treatment, talk with your doctor or pharmacist.

Cialis and lab tests

There are no specific reports of lab tests interacting with Cialis. For more information about having certain lab tests while taking Cialis, talk with your doctor or pharmacist.

Cialis interaction with cannabis or CBD

Cannabis (marijuana) and cannabis products, such as cannabidiol (CBD), have been specifically reported to interact with Cialis.

The exact effect of cannabis products on Cialis may vary from person to person. In some cases, cannabis products may decrease the level of Cialis in the body, which could cause the drug to be less effective than usual.

In other cases, cannabis products may raise the level of Cialis in the body. This could increase your risk of side effects from Cialis. (To learn about possible side effects of Cialis, see this article.)

Before you start treatment with Cialis, tell your doctor and pharmacist if you take cannabis. By sharing this information with them, you may help prevent possible interactions.

Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.

Certain medical conditions and other factors may increase the risk of interactions with Cialis. Before you take Cialis, be sure to talk with your doctor about your health history. Cialis may not be the right treatment option for you if you have certain medical conditions or other factors affecting your health.

Health conditions or factors that might interact with Cialis include the following:

Misshaped penis. Before starting treatment with Cialis, tell your doctor if you have a condition that affects the shape of your penis, such as Peyronie’s disease. Such conditions can increase your risk of priapism as a side effect. Your doctor can help determine whether Cialis is a safe treatment option for you.

Heart problems or stroke. Doctors typically will not prescribe Cialis if you have a heart problem or have had a stroke. Examples of heart problems include having heart failure in the past 6 months or a heart attack in the past 90 days.

Cialis is also not recommended in people with problems such as:

It’s not known whether Cialis is safe if you have any of these conditions. If you do, your doctor will likely prescribe a treatment other than Cialis.

Liver or kidney problems. If you have a liver or kidney problem, be sure to tell your doctor before taking Cialis. Examples of these problems include liver failure and kidney failure. Your doctor may give you a lower dosage of Cialis than what’s typically prescribed. (For details about the dosage of Cialis, see this article.)

Bleeding problems. Before taking Cialis, tell your doctor if you have a bleeding problem. An example is hemophilia. Your doctor can advise you on whether Cialis is a safe treatment option for you.

Blood cancers or blood cell problems. Before taking Cialis, tell your doctor if you have a blood cancer. Examples include multiple myeloma and leukemia. Also tell them if you have certain blood cell problems, such as sickle cell anemia. These conditions could increase your risk of priapism as a side effect. Your doctor can help determine if Cialis is right for you.

Peptic ulcers. If you have a peptic ulcer, talk with your doctor before taking Cialis. You may have an increased risk of bleeding with the drug. Your doctor can advise you on whether Cialis is safe to take.

Eye problems. In rare cases, Cialis can cause vision loss or other serious eye problems. If you already have an eye problem, you may have an increased risk of eye side effects with the drug. Before taking Cialis, tell your doctor if you have a problem with your retina or optic nerve. This includes conditions such as retinitis pigmentosa. They can help determine whether it’s safe for you to take Cialis.

Allergic reaction. If you’ve had an allergic reaction to Cialis or any of its ingredients, your doctor will likely not prescribe Cialis. For details, see “When to avoid Cialis” above.

Pregnancy. Cialis is not approved for use in females.* It’s not known if the drug is safe to use during pregnancy. You can talk with your doctor to learn more.

Breastfeeding. Cialis is not approved for use in females.* It’s not known if Cialis passes into breast milk. For additional information about Cialis and breastfeeding, talk with your doctor.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to sex assigned at birth.

Here are some frequently asked questions about Cialis and possible interactions.

Does Cialis interact with NSAIDs, such as ibuprofen or meloxicam?

There’s no known interaction between Cialis and nonsteroidal anti-inflammatory drugs (NSAIDs). Although NSAIDs are typically used to treat pain, they can also be used for inflammation.

If you’re interested in treating inflammation or pain while taking Cialis, talk with your doctor or pharmacist.

Can I drink coffee while taking Cialis?

Coffee and Cialis are not known to interact with each other.

Coffee often contains high amounts of caffeine. The results of one study found that consuming caffeine may lower the risk of erectile dysfunction (ED), which Cialis is used to treat. However, it’s unknown whether coffee or caffeine is effective for treating this condition.

If you’d like to learn more about Cialis and coffee, talk with your doctor.

Do Cialis and finasteride interact?

Cialis is not known to interact with the drug finasteride (Propecia, Proscar). Finasteride is used to treat conditions such as baldness and benign prostatic hyperplasia.

Finasteride may cause ED as a side effect. Cialis is used to treat ED. If you develop ED while taking finasteride, your doctor may prescribe medication to ease the side effect. This may include Cialis. Your doctor can tell you more.

Is there an interaction between Cialis and Xanax?

There’s no known interaction between Cialis and alprazolam (Xanax).

Xanax may cause sexual side effects, including changes in libido (sex drive). Having a low libido could result in ED. Therefore, it’s possible that taking Xanax could result in ED. If you have ED due to Xanax, your doctor may prescribe Cialis to treat your condition.

If you have other questions about Cialis and Xanax, talk with your doctor or pharmacist.

Can I take Cialis with omeprazole?

Cialis and omeprazole (Prilosec) are not known to interact with each other. Omeprazole is used to treat certain digestive problems, such as acid reflux.

The results of one report suggest that ED is a possible side effect of omeprazole. If you have ED that’s related to omeprazole, your doctor can recommend the right treatment option for you. This may include taking Cialis.

You can take certain steps to help prevent interactions with Cialis. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. For example, you should plan the following:

Let them know if you drink alcohol or take cannabis.
Tell them about any other medications you take, as well as any supplements, herbs, and vitamins.
Create a medication list , which your doctor and pharmacist can help you fill out.

It’s also important to read the label of Cialis and other paperwork that comes with the drug. The label may have colored stickers that mention an interaction. And the paperwork, sometimes called the prescribing information , may contain details about interactions. If this information is difficult to understand, ask your doctor or pharmacist to help explain it.

You can also help prevent interactions with Cialis by taking it exactly as your doctor prescribes.

Besides learning about interactions, you may want to find out more about Cialis. These resources might help:

Overview of Cialis. For a general overview of Cialis, read this article.
Side effects. If you’re interested in the side effects of Cialis, see this article. Another option is to refer to the Cialis prescribing information.
Dosage specifics. You can refer this article to learn about the dosage of Cialis.
Drug comparison. Find out how Cialis compares with Viagra, Levitra, and Adcirca.
Facts about your condition. To learn more about your condition, see our men’s health hub.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

Last medically reviewed on July 16, 2022

How we reviewed this article:

Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. We avoid using tertiary references. We link primary sources — including studies, scientific references, and statistics — within each article and also list them in the resources section at the bottom of our articles. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

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