The Science Behind Sildenafil's Mechanism of Action
How PDE5 Inhibitors Function
Sildenafil belongs to a class of medications called phosphodiesterase type 5 (PDE5) inhibitors. During sexual arousal, the body naturally releases nitric oxide in the penis, which triggers the production of cyclic guanosine monophosphate (cGMP). This chemical messenger relaxes smooth muscle tissue and dilates blood vessels, allowing increased blood flow to create an erection.
The PDE5 enzyme normally breaks down cGMP, ending the erection. Sildenafil blocks this enzyme, allowing cGMP levels to remain elevated for longer periods, which can help maintain improved blood flow when sexually stimulated.
Sexual Stimulation Still Required
It's important to understand that sildenafil does not automatically cause erections. Sexual arousal and stimulation are still necessary for the medication to be effective. The drug simply enhances the body's natural erectile response when arousal occurs.
Timing and Duration of Effects
Sildenafil typically begins working within 30-60 minutes of taking the tablet. The effects may last for 4-6 hours, though this doesn't mean an erection will persist for this entire duration. Rather, it represents the window during which the medication may help facilitate erections when sexual stimulation occurs.
Taking sildenafil with fatty meals may delay absorption and onset of action. For optimal results, consider taking the medication on an empty stomach or with a light meal.
Dosage Options Available
EverydayMeds offers sildenafil in three strengths: 25mg, 50mg, and 100mg tablets. The typical starting dose is 50mg, which can be adjusted based on individual response and tolerability. Only one dose should be taken within a 24-hour period.
At checkout, patients can choose between branded Viagra or generic sildenafil - both contain the same active ingredient but sildenafil offers a more cost-effective alternative.
Who May Be Suitable for Treatment
Sildenafil may be appropriate for adult men experiencing erectile dysfunction, following a clinical consultation. EverydayMeds requires completion of an online assessment with a UK-licensed prescriber to evaluate suitability.
The medication is not suitable for everyone. Men taking nitrate medications, those with severe cardiovascular conditions, or certain other medical conditions may not be candidates for sildenafil treatment. A thorough medical assessment helps ensure safe prescribing.
Over-the-Counter Availability
While prescription sildenafil is available in 25mg, 50mg, and 100mg strengths, Viagra Connect (50mg sildenafil) can be purchased over-the-counter from pharmacies following a consultation with a pharmacist. However, the prescription-only versions offer greater dosage flexibility and ongoing medical oversight.
