Legal Status of Sildenafil Around the World

From the Department of Urology, Boston University Medical Center, Boston (I.G. ); the Department of Urology, University of California, San Francisco (T.F.L. ); the Department of Urology, University of Southern California, Los Angeles, and the Male Clinic, Santa Monica, Calif. (H.P.-N.); the Department of Psychiatry, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, N.J. ); the Department of Urology, University of Virginia, Charlottesville (W.D.S.

• Sildenafil has been shown to aid men with diabetes-related ED.
• The drug may also reduce blood pressure temporarily.
• Some men may not respond to sildenafil due to various health factors.
• It is recommended to take sildenafil on an empty stomach for faster effects.
• Overdose symptoms include dizziness, fainting, and pain in the chest.
• Sildenafil should not be used with other erectile dysfunction medications simultaneously.
• Patients should inform their doctor if they experience prolonged erections.
• Certain medical conditions require cautious use of sildenafil.
• The medication can sometimes cause changes in color perception.
• Always check the expiration date before using sildenafil pills.

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Medical uses

What should I do if I accidentally use too much sildenafil?

Multi-view semi-supervised adversarial attention network for drug repurposing, Computer Methods and Programs in Biomedicine, 282, (109406), (2026). Multi‐Target Mechanisms of Moroccan Aphrodisiac Plants: An Integrative Computational and Phytochemical Investigation, Food Science & Nutrition, 14, 5, (2026). Artificial intelligence in drug research and development: a review of methods and applications in drug repurposing, Briefings in Bioinformatics, 27, 3, (2026). Endocrine-metabolic crosstalk in erectile dysfunction: mechanistic insights and therapeutic implications, International Journal of Impotence Research, (2026).

Therapeutic applications of phosphodiesterase inhibitors in male reproductive health: narrative review, Sexual Medicine Reviews, 14, 2, (2026). Oral suspension versus tablet sildenafil for erectile dysfunction: a prospective multicenter comparative study on patient satisfaction, International Journal of Impotence Research, (2026). Low‐intensity shockwave therapy for erectile dysfunction: An abridged Cochrane review, BJU International, 137, 6, (949-957), (2026). Current state of the problem, Andrology and Genital Surgery, 25, 4, (33-40), (2026).

• Sildenafil helps improve erections by relaxing penile muscles.
• The drug's popularity increased rapidly after approval in the late 1990s.
• It is part of a class of medications called PDE5 inhibitors.
• Sildenafil's development marked a breakthrough for men's health.
• There are ongoing studies to expand sildenafil's therapeutic uses.
• Regular medical check-ups are advised for long-term sildenafil use.
• Generic sildenafil has made treatment more affordable worldwide.
• It’s crucial to adhere to prescribed doses to avoid adverse effects.
• The medication is often taken about 30 minutes before sexual activity.
• Using sildenafil responsibly can improve quality of life for many men.

Emerging Trends and Research Focus in Erectile Dysfunction Treatment: A 1993–2023 Bibliometric Analysis, Andrologia, 2026, 1, (2026). [1][2][4][5][7][8][10][24][27][33][41][56][57][67][91][131] Brand Name: Vybrique, ViagraClasses: Phosphodiesterase Type 5 Inhibitors (24:08.12), Phosphodiesterase type 5 inhibitors (48:48.24) Sildenafil citrate (Viagra® and generic equivalents) is used orally for the treatment of erectile dysfunction (ED, impotence).

More about sildenafil

Revatio for Oral Suspension

[1][4][6][7][8][9][10][25][33][34][67][81][102][104][105][107][108][112][118][126][127][128][129][130][131][132][133][134][140][142][143][144][189] A thorough medical, sexual and psychosocial history, physical examination, and selective laboratory testing should be undertaken to diagnose ED, determine potential underlying causes, exclude potentially reversible or treatable causes (e.g., hypogonadism with inadequate testosterone replacement, hyperprolactinemia, drug-induced dysfunction, dyslipidemias, alcoholism, other substance abuse, hypertension, thyroid disease, cardiovascular or cerebrovascular disease, neurologic disease, adrenal dysfunction, psychologic dysfunction, marital discord, smoking), and identify appropriate treatment in conjunction with or prior to initiating vasoactive therapy (e.g., PDE 5 type inhibitor). [12][28][30][31][57][65][66][70][78][83][94][144][145][160][161][189][601][602][603] A review of the patient's current drug regimens should be conducted to detect possible drug-induced ED (e.g., certain antihypertensive, antidepressant, antipsychotic, or antiarrhythmic agents); it may be possible to substitute alternative drug(s) that lessen the risk of such dysfunction. [12][28][70][81][118][144][161][602][603] In instances where substitution therapy is not feasible, concomitant vasoactive therapy with a PDE 5 type inhibitor may promote patient compliance by counteracting ED as an adverse effect. [12][28][70][81][118][144][161][602][603] Efficacy of sildenafil is variable in patients with ED, in part depending on the underlying etiology, severity, and dose employed, but the drug generally appears to be effective in restoring sexual function to an acceptable level in the majority of treated men.

Does Dual Combination Therapy Work?

[1][7][8][9][10][25][33][34][65][76][81][101][104][105][126][127][131][142][143][144] The erectile response generally increases with increasing sildenafil dose and plasma drug concentration, with response becoming greater at 50- and 100-mg doses than at 25 mg.[1][8][9][33][126][130][131][155] Analyses of subgroups of patients with ED indicate that efficacy of sildenafil is not affected by race or age, duration of ED, or duration of select underlying disease states (e.g., diabetes mellitus), and the drug has been effective in a broad range of patients with ED, including those with a history of coronary artery disease (e.g., coronary artery bypass graft [CABG]), hypertension, other cardiac disease (including ischemic heart disease), peripheral vascular disease, type 1 or 2 diabetes mellitus, depression, radical prostatectomy, prostate brachytherapy, transurethral resection of the prostate (TURP), spina bifida, spinal cord injury, and in patients taking antidepressants, antipsychotics, diuretics, and antihypertensive agents. [1][25][30][33][34][93][101][102][104][105][107][108][112][118][126][127][128][129][130][131][132][133][134][140][144] Pooled data from numerous fixed-dose and flexible-dose studies in men with ED secondary to a broad spectrum of organic and psychogenic causes showed increases in mean rates of successful intercourse (total successes divided by total attempts) to about 66-69% in those receiving sildenafil compared with about 20-22% for placebo. Erectile response to sildenafil is better in patients whose erectile function is less impaired at treatment initiation (e.g., those with some spontaneous successful intercourse, with partial erections, with erections during sleep, or with psychogenic causes). [1][33][105][145] In one flexible-dose study (dosage titration and maintenance up to 100 mg), mean scores for number of successful penetrations returned to 50 mg sildenafil price normal in a subgroup of patients with psychogenic causes of ED; however, mean scores for maintenance of erections during intercourse in these men were lower than in untreated healthy men. [33][34] In a study in men with ED secondary to radical prostatectomy receiving fixed-dose sildenafil (100 mg), response to therapy was greatest in those who had undergone bilateral-nerve-sparing surgery than in those who had undergone unilateral or non-nerve-sparing procedures.

Revatio Injection

[104][127] Pooled data from various clinical trials indicate that sildenafil improved the erections of 43% of patients with ED secondary to radical prostatectomy compared with 15% of those receiving placebo. [1][104] A pooled analysis of 10 placebo-controlled studies of men with severe ED (organic etiology in 60%, psychogenic in 15%, and mixed in 25% of patients) treated with sildenafil (50-100 mg in fixed- or flexible-dose studies) indicated that 48% of the patients usually had erections sufficient for intercourse (score of 4, with 0 being unsuccessful and 5 being almost always successful) after treatment with sildenafil, compared with 8% of those receiving placebo. [76][127] In several randomized, double-blind, placebo-controlled studies in patients receiving sildenafil (flexible doses up to 100 mg or fixed doses ranging from 10-100 mg for 12 weeks) for the treatment of ED attributed to complications of diabetes mellitus, complications of spinal cord injury, or psychogenic causes, 48, 59, or 70% of all attempts at intercourse were successful, respectively, compared with 12, 13, or 29% of all attempts in those receiving placebo. [1][7][8][9][10][25][33][93] In these studies, sildenafil improved several aspects of sexual function including frequency, firmness, and maintenance of erection; frequency of orgasm; satisfaction and enjoyment of intercourse; and overall relationship satisfaction. [1][8][9][33][94][107][130][131][142] Pooled data from fixed- and flexible-dose studies indicate that sildenafil (50 or 100 mg) has no effect on sexual desire (i.e., rates of attempted intercourse, which averaged about 2 per week), but the rate of success increased to an average of 1.3 events per patient per week from 0.4 events per week with placebo. [1][7][8][9][10][25][33][34][65][76][81][101][104][105][126][127][131][142][143][144] The erectile response generally increases with increasing sildenafil dose and plasma drug concentration, with response becoming greater at 50- and 100-mg doses than at 25 mg.[1][8][9][33][126][130][131][155] Analyses of subgroups of patients with ED indicate that efficacy of sildenafil is not affected by race or age, duration of ED, or duration of select underlying disease states (e.g., diabetes mellitus), and the drug has been effective in a broad range of patients with ED, including those with a history of coronary artery disease (e.g., coronary artery bypass graft [CABG]), hypertension, other cardiac disease (including ischemic heart disease), peripheral vascular disease, type 1 or 2 diabetes mellitus, depression, radical prostatectomy, prostate brachytherapy, transurethral resection of the prostate (TURP), spina bifida, spinal cord injury, and in patients taking antidepressants, antipsychotics, diuretics, and antihypertensive agents.

What should I know about storage and disposal of this medication?

Therapeutic applications of phosphodiesterase inhibitors in male reproductive health: narrative review, Sexual Medicine Reviews, 14, 2, (2026). Oral suspension versus tablet sildenafil for erectile dysfunction: a prospective multicenter comparative study on patient satisfaction, International Journal of Impotence Research, (2026). Low‐intensity shockwave therapy for erectile dysfunction: An abridged Cochrane review, BJU International, 137, 6, (949-957), (2026). Current state of the problem, Andrology and Genital Surgery, 25, 4, (33-40), (2026). Emerging Trends and Research Focus in Erectile Dysfunction Treatment: A 1993–2023 Bibliometric Analysis, Andrologia, 2026, 1, (2026).

FDA Approval Information

[1][2][4][5][7][8][10][24][27][33][41][56][57][67][91][131] Brand Name: Vybrique, ViagraClasses: Phosphodiesterase Type 5 Inhibitors (24:08.12), Phosphodiesterase type 5 inhibitors (48:48.24) Sildenafil citrate (Viagra® and generic equivalents) is used orally for the treatment of erectile dysfunction (ED, impotence). [1][4][6][7][8][9][10][25][33][34][67][81][102][104][105][107][108][112][118][126][127][128][129][130][131][132][133][134][140][142][143][144][189] A thorough medical, sexual and psychosocial history, physical examination, and selective laboratory testing should be undertaken to diagnose ED, determine potential underlying causes, exclude potentially reversible or treatable causes (e.g., hypogonadism with inadequate testosterone replacement, hyperprolactinemia, drug-induced dysfunction, dyslipidemias, alcoholism, other substance abuse, hypertension, thyroid disease, cardiovascular or cerebrovascular disease, neurologic disease, adrenal dysfunction, psychologic dysfunction, marital discord, smoking), and identify appropriate treatment in conjunction with or prior to initiating vasoactive therapy (e.g., PDE 5 type inhibitor). [12][28][30][31][57][65][66][70][78][83][94][144][145][160][161][189][601][602][603] A review of the patient's current drug regimens should be conducted to detect possible drug-induced ED (e.g., certain antihypertensive, antidepressant, antipsychotic, or antiarrhythmic agents); it may be possible to substitute alternative drug(s) that lessen the risk of such dysfunction. [12][28][70][81][118][144][161][602][603] In instances where substitution therapy is not feasible, concomitant vasoactive therapy with a PDE 5 type inhibitor may promote patient compliance by counteracting ED as an adverse effect. [12][28][70][81][118][144][161][602][603] Efficacy of sildenafil is variable in patients with ED, in part depending on the underlying etiology, severity, and dose employed, but the drug generally appears to be effective in restoring sexual function to an acceptable level in the majority of treated men. [1][25][30][33][34][93][101][102][104][105][107][108][112][118][126][127][128][129][130][131][132][133][134][140][144] Pooled data from numerous fixed-dose and flexible-dose studies in men with ED secondary to a broad spectrum of organic and psychogenic causes showed increases in mean rates of successful intercourse (total successes divided by total attempts) to about 66-69% in those receiving sildenafil compared with about 20-22% for placebo. Erectile response to sildenafil is better in patients whose erectile function is less impaired at treatment initiation (e.g., those with some spontaneous successful intercourse, with partial erections, with erections during sleep, or with psychogenic causes).

• Do not take sildenafil if you have a history of heart attack or stroke.
• Women and children should not use sildenafil products.
• The medication can cause temporary vision disturbances, including blue-tinted vision.
• Always consult a healthcare provider before starting sildenafil therapy.
• Use caution when driving or operating machinery after taking sildenafil.
• Sildenafil is contraindicated in people with hypersensitivity to the drug.
• Some users report improved erectile function within 15 minutes.
• It is essential to stay hydrated, but avoid consuming large amounts of alcohol.
• Men with certain health conditions should undergo a medical exam before use.
• Overuse or misuse of sildenafil can lead to serious health complications.

[1][33][105][145] In one flexible-dose study (dosage titration and maintenance up to 100 mg), mean scores for number of successful penetrations returned to 50 mg sildenafil price normal in a subgroup of patients with psychogenic causes of ED; however, mean scores for maintenance of erections during intercourse in these men were lower than in untreated healthy men. [33][34] In a study in men with ED secondary to radical prostatectomy receiving fixed-dose sildenafil (100 mg), response to therapy was greatest in those who had undergone bilateral-nerve-sparing surgery than in those who had undergone unilateral or non-nerve-sparing procedures. [104][127] Pooled data from various clinical trials indicate that sildenafil improved the erections of 43% of patients with ED secondary to radical prostatectomy compared with 15% of those receiving placebo.

• Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor.
• The drug was first approved by the FDA in 1998.
• It can be purchased online but requires a prescription in most countries.
• Generic versions of sildenafil are typically cheaper than brand-name Viagra.
• Proper storage involves keeping it at room temperature away from moisture.
• Sildenafil does not protect against sexually transmitted diseases.
• Lifestyle changes like exercise and healthy eating can enhance results.
• Combining sildenafil with other ED treatments should be discussed with a doctor.
• It's important to inform your doctor about all medications you take.
• Sildenafil is not an aphrodisiac and requires sexual stimulation to work.

[1][104] A pooled analysis of 10 placebo-controlled studies of men with severe ED (organic etiology in 60%, psychogenic in 15%, and mixed in 25% of patients) treated with sildenafil (50-100 mg in fixed- or flexible-dose studies) indicated that 48% of the patients usually had erections sufficient for intercourse (score of 4, with 0 being unsuccessful and 5 being almost always successful) after treatment with sildenafil, compared with 8% of those receiving placebo. [76][127] In several randomized, double-blind, placebo-controlled studies in patients receiving sildenafil (flexible doses up to 100 mg or fixed doses ranging from 10-100 mg for 12 weeks) for the treatment of ED attributed to complications of diabetes mellitus, complications of spinal cord injury, or psychogenic causes, 48, 59, or 70% of all attempts at intercourse were successful, respectively, compared with 12, 13, or 29% of all attempts in those receiving placebo. [1][7][8][9][10][25][33][93] In these studies, sildenafil improved several aspects of sexual function including frequency, firmness, and maintenance of erection; frequency of orgasm; satisfaction and enjoyment of intercourse; and overall relationship satisfaction.

Other targets: Therapeutic roles

[1][8][9][33][94][107][130][131][142] Pooled data from fixed- and flexible-dose studies indicate that sildenafil (50 or 100 mg) has no effect on sexual desire (i.e., rates of attempted intercourse, which averaged about 2 per week), but the rate of success increased to an average of 1.3 events per patient per week from 0.4 events per week with placebo.

Are There Any Downsides to Combination Therapy?

From the Department of Urology, Boston University Medical Center, Boston (I.G. ); the Department of Urology, University of California, San Francisco (T.F.L. ); the Department of Urology, University of Southern California, Los Angeles, and the Male Clinic, Santa Monica, Calif. (H.P.-N.); the Department of Psychiatry, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, N.J. ); the Department of Urology, University of Virginia, Charlottesville (W.D.S.

Are there reviews from people who had side effects with 50-mg or 100-mg sildenafil tablets?

Select the format you want to export the citation of this publication. Multi-view semi-supervised adversarial attention network for drug repurposing, Computer Methods and Programs in Biomedicine, 282, (109406), (2026). Multi‐Target Mechanisms of Moroccan Aphrodisiac Plants: An Integrative Computational and Phytochemical Investigation, Food Science & Nutrition, 14, 5, (2026). Artificial intelligence in drug research and development: a review of methods and applications in drug repurposing, Briefings in Bioinformatics, 27, 3, (2026). Endocrine-metabolic crosstalk in erectile dysfunction: mechanistic insights and therapeutic implications, International Journal of Impotence Research, (2026). [1][8][33][131] In part, the absence of an effect on sexual desire may be attributed to the fact that men enrolling in ED studies generally have a near-normal level of sexual desire upon study entry. [33][107][130][131] Improvement in erectile function sufficient for successful intercourse can be achieved with sildenafil in a substantial percentage of patients with ED, and the strength and duration of erection achieved with the drug in such patients approached those achieved in untreated healthy men. Sildenafil also has been effective in a limited number of men with temporary ED associated with the stress of providing a sperm sample (e.g., for intrauterine insemination or in vitro fertilization during assisted reproduction). [143] In men with a history of such temporary dysfunction, planned use of sildenafil for subsequent attempts at obtaining a sperm specimen may improve attainment of an erection adequate for self-stimulated ejaculation.

While most males with ED respond to oral sildenafil therapy, treatment failures do occur; pooled data from various placebo-controlled, dose-response, or open-label studies (25-100 mg for 6-12 months) indicate that up to 5% of patients discontinued therapy because of lack of effectiveness. [1][7][33][69][93][104][107][128][131][132][163][165] Information on the long-term effects of sildenafil is limited, and thus the optimum duration of therapy is not known.

When oral medications might not be safe

[1][8][33][131] In part, the absence of an effect on sexual desire may be attributed to the fact that men enrolling in ED studies generally have a near-normal level of sexual desire upon study entry. [33][107][130][131] Improvement in erectile function sufficient for successful intercourse can be achieved with sildenafil in a substantial percentage of patients with ED, and the strength and duration of erection achieved with the drug in such patients approached those achieved in untreated healthy men. Sildenafil also has been effective in a limited number of men with temporary ED associated with the stress of providing a sperm sample (e.g., for intrauterine insemination or in vitro fertilization during assisted reproduction). [143] In men with a history of such temporary dysfunction, planned use of sildenafil for subsequent attempts at obtaining a sperm specimen may improve attainment of an erection adequate for self-stimulated ejaculation. While most males with ED respond to oral sildenafil therapy, treatment failures do occur; pooled data from various placebo-controlled, dose-response, or open-label studies (25-100 mg for 6-12 months) indicate that up to 5% of patients discontinued therapy because of lack of effectiveness.

Last Reviewed Date

[1][7][33][69][93][104][107][128][131][132][163][165] Information on the long-term effects of sildenafil is limited, and thus the optimum duration of therapy is not known. [1][33][81][128][132] In clinical studies, sildenafil was used in patients ranging in age from 19-87 years of age with a duration of ED averaging 5 years. [1] In several long-term and open-label studies, sildenafil remained effective for at least 0.5-4 years, with no evidence of tachyphylaxis during long-term use, and current evidence indicates that continued therapy is necessary as long as the condition persists (i.e., sildenafil is not a cure for ED). The safety and efficacy of sildenafil in combination with other treatments for ED have not been established. [1][33][81][128][132] In clinical studies, sildenafil was used in patients ranging in age from 19-87 years of age with a duration of ED averaging 5 years. [1] In several long-term and open-label studies, sildenafil remained effective for at least 0.5-4 years, with no evidence of tachyphylaxis during long-term use, and current evidence indicates that continued therapy is necessary as long as the condition persists (i.e., sildenafil is not a cure for ED). The safety and efficacy of sildenafil in combination with other treatments for ED have not been established.