Avanafil works by inhibiting PDE5, an enzyme that breaks down cyclic GMP (cGMP). By blocking this enzyme, Avanafil increases the levels of cGMP, leading to enhanced blood flow to the penis and facilitating an erection in response to sexual stimulation.Onset Time: Typically starts working within 15-30 minutes after ingestion.Duration: The effects usually last for 4-6 hours, although some users may experience effects for a longer duration.