Zenegra 100 mg is a generic form of Viagra, an erectile dysfunction (ED) medication. It is a phosphodiesterase type 5 (PDE5) inhibitor, which works by increasing blood flow to the penis to help a man get and keep an erection. Zenegra 100 mg is available in the form of tablets and is taken orally with a glass of water. It should be taken approximately 30 minutes before sexual activity. The...