Erectile dysfunction (ED) affects an estimated 30 million men in the United States — with prevalence increasing with age and with comorbidities including diabetes, cardiovascular disease, hypertension, and obesity. ED is now recognised as an early marker of cardiovascular disease, as the penile arteries (which are small-calibre) manifest atherosclerotic disease earlier than the larger coronary arteries — an ED diagnosis should prompt cardiovascular risk factor screening. Effective pharmacological treatment has been available since sildenafil's 1998 FDA approval, and the class of PDE5 inhibitors has become the cornerstone of ED pharmacotherapy.
PDE5 inhibitors (sildenafil, tadalafil, vardenafil, avanafil) work by inhibiting phosphodiesterase type 5 — the enzyme that degrades cyclic GMP (cGMP) in smooth muscle of corpus cavernosum. In the presence of sexual stimulation, nitric oxide activates guanylate cyclase, producing cGMP, which relaxes smooth muscle and allows blood engorgement. PDE5 inhibitors prolong cGMP signalling, enhancing and sustaining erection in response to sexual stimulation. They do not produce erections without sexual stimulation.
Important note on unlicensed products: This category also includes pages on products sold online without regulatory approval (Kamagra, Sildalis, Tadapox). These products are not FDA-approved, may contain incorrect doses or contaminants, and carry serious health risks. These pages exist to inform patients of those risks and redirect toward licensed prescriptions through a qualified healthcare provider.
Sexual Health Medications Available at Lucas Clinic
- Dapoxetine — short-acting SSRI for premature ejaculation; licensed in EU/UK/Australia; not FDA-approved in US; 30/60 mg tablets; take 1–3 hours before sexual activity
- Kamagra (Sildenafil) — unregulated, unlicensed sildenafil product from Ajanta Pharma; not FDA/MHRA/EMA approved; information on counterfeit medicine risks
- Levitra (Vardenafil) — Rx PDE5 inhibitor; 5/10/20 mg tablets; onset 30–60 min; for erectile dysfunction; also available as Staxyn 10 mg ODT
- Sildalis — combination sildenafil + tadalafil; not FDA/EMA approved; informational page on regulatory status and risks
- Tadapox — combination tadalafil + dapoxetine; not FDA approved; informational page on regulatory status and risks
Disclaimer: This page is for general informational purposes only and does not constitute medical advice. Always consult a licensed healthcare professional before making any treatment decisions. See our full disclaimer.