Sildenafil
Viagra · Revatio · Silvasta
Half-life
4 hr
Time to Peak
1 hr
Steady State
~1 days
Bioavailability
41%
Dose Range
25–100 mg
Frequency
As needed
Overview
PDE5 inhibitor. FDA-approved for erectile dysfunction and pulmonary arterial hypertension. The original and most widely recognised PDE5 inhibitor. Shorter-acting than tadalafil (~4–6 hour effective window) — typically used as-needed rather than daily. TRT/AAS community uses it for ED management on cycle or post-PCT. Some users prefer sildenafil for acute use; tadalafil for daily cardiovascular benefit. Harm reduction: Do not combine with nitrates. Food (especially high-fat meals) delays absorption by ~1 hour. Take 30–60 minutes before intended use.
Mechanism of Action
Selective phosphodiesterase type 5 (PDE5) inhibitor. Same mechanism as tadalafil but shorter duration and slightly different selectivity profile. More selective for PDE6 (retinal) than tadalafil — may cause transient visual changes (blue tinge) at higher doses.
Dosing Information
| Route | Dose Range | Half-life | Tmax | Frequency |
|---|---|---|---|---|
| Oral | 25–100 mg | 4 hr | 1 hr | As needed |
Storage & Handling
Room temperature — Store at 25C (77F). Protect from moisture.
Used in Regimens
Sildenafil is not currently part of any catalog regimen.
Data Sources
- FDA Label Viagra (sildenafil) FDA Prescribing Information
Related Tools
Track Sildenafil with Doseline
Reminders, medication level charts, injection site rotation, and protocol tracking — all free, all private.
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