Viagra 50mg Tablet contains Sildenafil Citrate (50mg), a phosphodiesterase type 5 (PDE5) inhibitor used to treat erectile dysfunction (ED) in men. Sildenafil works by increasing blood flow to the penis during sexual stimulation, resulting in an erection. Common side effects include headache, flushing, dizziness, and upset stomach. The tablet is typically taken about 30 to 60 minutes before sexual activity, and its effects can last for up to 4 hours. It is important to follow the prescribed dosage and avoid taking it with nitrates or certain other medications. Consult a healthcare provider for any severe or persistent side effects or if the erection lasts longer than 4 hours (priapism).