Valif 20 mg is a medication used to treat erectile dysfunction (ED) in men. It contains the active ingredient Vardenafil, which is a phosphodiesterase type 5 (PDE5) inhibitor. Vardenafil works by increasing blood flow to the penis during sexual stimulation, allowing a man to achieve and maintain an erection. Common side effects of Vardenafil may include headache, facial flushing, indigestion, nasal congestion, muscle aches, and back pain. If you experience severe or persistent side effects, contact your healthcare provider.