Avana 100 mg is a medication used to treat erectile dysfunction (ED) and contains Avanafil, a PDE5 inhibitor similar to Sildenafil (Viagra), Tadalafil (Cialis), and Vardenafil (Levitra). Avanafil works by blocking the enzyme phosphodiesterase type 5 (PDE5), which helps to relax the blood vessels in the penis and increase blood flow, facilitating an erection in response to sexual stimulation.