Sildenafil (C4)
sin-DIF-uh-le
Category
Compound type
Phase / Status
FDA approved (brand name Viagra). Generic available. The OG ED drug that started the PDE5 revolution.
Standard Dose
As needed, 30-60 min before
Half-life
Plasma elimination
Route(s)
Oral
Research Stage
Regulatory approval granted; post-market monitoring ongoing.
Overview
Sildenafil helps blood vessels relax so blood flow can increase. It tends to start working sooner than tadalafil, but the practical effect window is shorter (often a few hours).
Plain-language summary
Sildenafil helps blood vessels relax so blood flow can increase. It tends to start working sooner than tadalafil, but the practical effect window is shorter (often a few hours).
Administration Routes
- Oral
Also known as
Mechanisms
Phosphodiesterase type 5 (PDE5) inhibitor - increases blood flow by relaxing blood vessels. Basically opens up the blood pipes where you need it most.
Detailed mechanism
Phosphodiesterase type 5 (PDE5) inhibitor - increases blood flow by relaxing blood vessels. Modulates cellular pathways and enzyme activity to produce therapeutic effects at the molecular level.
Safety
Side effects
- Headache
- Flushing
- Nasal congestion
- Indigestion
- Vision changes (rare)
- Dizziness
Reported benefits
- Fast acting (30-60 min)
- Treats erectile dysfunction
- Increases blood flow
- May help with pumps
- Well-studied safety profile
Safety profile
Well-characterized safety profile from extensive clinical use and trials.
Clinical trials
Completed clinical trials leading to FDA or regulatory approval.
Structure
Verified structure
Sildenafil (C4)
Exact 2D structure can be rendered from a PubChem-backed canonical SMILES string.
- Chemical Formula
- C22H30N6O4S
- Molecular Weight
- 347.44 g/mol
- CAS Number
- 139755-83-2
- InChIKey
- KYIZVGATHRLFFT-UHFFFAOYSA-N
Stack Context
Stacks with
Comparison context
Sildenafil was originally developed as a blood pressure medication, the erectile effect was a happy accident. Tadalafil (Cialis) lasts 36 hours versus sildenafil's 4-6 hours, but sildenafil hits faster and harder. Unlike PT-141, which creates desire through the brain, sildenafil only affects the physical response. The two can be combined for both mental and physical effect.
References
- 1View source
Sildenafil for erectile dysfunction: pivotal placebo-controlled trial (NEJM)
1998
- 2View source
Sildenafil in men with erectile dysfunction (Annals of Internal Medicine)
1999
This profile summarizes research literature for education only. It is not medical advice, and it does not diagnose, treat, or recommend a dose. Consult a qualified professional before changing a protocol.