Viagra, or sildenafil, works by inhibiting an enzyme called phosphodiesterase-5 (PDE5). This enzyme normally breaks down cGMP, a chemical that relaxes the muscles in the blood vessels of the penis. By blocking PDE5, Viagra increases cGMP levels, leading to improved blood flow and facilitating an erection.
Common Side Effects
While Viagra is generally well-tolerated, some men experience side effects. These commonly include headache, facial flushing, nasal congestion, and visual disturbances like blurred vision or sensitivity to light. Less frequent side effects can involve indigestion, muscle aches, or dizziness. The severity and frequency of these vary significantly between individuals. Always discuss any concerns with your doctor.
Less Common Side Effects
More rarely, Viagra can cause more serious side effects, including a prolonged erection (priapism), sudden vision loss, or hearing loss. Seek immediate medical attention if you experience any of these.
