Rankings / Libido

Sildenafil (Viagra)

Libido · PDE5 inhibitor

Tier A

pde5prescription
8.4 / 10
Tier A
Ev 10.0 Bn 10.0 Sf 5.0 Ax 6.0

What this is

Generic since 2017 — dramatic price drop. Fang 2021 and others show observational Alzheimer risk reduction in PDE5i users — mechanism via cerebral blood flow and Aβ modulation plausible. Take food separation seriously — high-fat meal delays absorption >1 hour. Do not combine with any nitrate.

Mechanism

Selective phosphodiesterase-5 inhibitor; prevents cGMP breakdown → sustained smooth muscle relaxation in corpus cavernosum → erection (upon sexual stimulation, not spontaneous); also pulmonary vasodilation

Dose & route

25-100 mg PO 30-60 min before activity; take on empty stomach for faster onset

This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.