If an erection is painful or lasts longer than four hours (priapism), immediate emergency medical care is required to prevent permanent tissue damage. 3. Usage Considerations

Estrogen and testosterone blockers often lead to changes in erectile firmness or duration. Sildenafil works by relaxing the blood vessels, allowing more blood to flow to the area during sexual arousal.

Providers specializing in transgender health can offer tailored advice on how Sildenafil interacts with specific hormone blockers or other transition-related medications.