From the Guidelines
The recommended dose of Sildenafil for erectile dysfunction is typically 50 mg taken approximately one hour before sexual activity, with a maximum frequency of once daily, as supported by the most recent and highest quality study available 1. When considering the treatment of erectile dysfunction with Sildenafil, it's essential to take into account the individual's health conditions and medication regimen. The dose can be adjusted between 25 mg and 100 mg based on effectiveness and tolerability.
- For older adults (over 65), those with liver or severe kidney impairment, or patients taking certain medications like protease inhibitors, a lower starting dose of 25 mg is recommended.
- Sildenafil works by enhancing the effects of nitric oxide, which relaxes muscles in the penis and increases blood flow, helping to achieve and maintain an erection when sexually stimulated.
- It should not be taken with nitrates (like nitroglycerin) as this combination can cause a dangerous drop in blood pressure.
- Common side effects include headache, flushing, indigestion, nasal congestion, and visual disturbances. However, for patients with pulmonary arterial hypertension (PAH), the FDA-approved dose of sildenafil is 20 mg administered orally 3 times daily, as indicated in the study by 1. It's crucial to note that management of erectile dysfunction should always be considered secondary to maintaining cardiovascular function, and treatment for ED should not negatively affect cardiovascular health, as emphasized in the recommendations by 1.
From the FDA Drug Label
DOSAGE & ADMINISTRATION The recommended dose of sildenafil tablets is 20 mg three times a day (TID). Administer sildenafil tablet doses 4-6 hours apart. In the clinical trial no greater efficacy was achieved with the use of higher doses. Treatment with doses higher than 20 mg TID is not recommended. The recommended dose of Sildenafil (Viagra) is 20 mg taken three times a day (TID), with doses administered 4-6 hours apart 2.
From the Research
Recommended Dose of Sildenafil
The recommended dose of Sildenafil (Viagra) is as follows:
- The usual starting dose is 50mg taken when needed, approximately 1 hour before sexual activity, and no more than once daily 3, 4.
- The maximum dose is 100mg when needed, once daily 3, 4.
- Lower doses, such as 25mg, may be used in elderly patients and those with hepatic or renal impairment, or receiving cytochrome P450 enzyme CYP3A4 inhibitors 3.
Special Considerations
- Patients with certain cardiovascular conditions, liver or kidney disease, and those taking medications that may prolong sildenafil's half-life may require caution when prescribing sildenafil 4.
- Men with known or suspected coronary artery disease may benefit from an exercise test to determine whether resumption of sexual activity with use of sildenafil is likely to be associated with an increased risk of myocardial ischemia 4.
- Sildenafil is effective and well-tolerated in men with erectile dysfunction, regardless of patient age, including men at least 75 years old 5.
Efficacy and Safety
- Sildenafil has been shown to be effective in improving erections and allowing successful penetrative sexual intercourse in men with erectile dysfunction 3, 6, 5.
- Common adverse events associated with sildenafil are transient and mild or moderate, and include headache, flushing, dyspepsia, nasal congestion, and abnormal vision 3, 5.
- The addition of l-arginine to sildenafil may demonstrate more efficacy than sildenafil alone for the treatment of erectile dysfunction patients 7.