Viracept (generic: nelfinavir) is a prescription medication used to treat human immunodeficiency virus (HIV) infection. Viracept is in a class of medicines called HIV protease inhibitors. Viracept works by blocking HIV protease (a protein-cutting enzyme), which is required for HIV to multiply.

This medication comes in tablet and powder forms. It is usually taken 2 to 3 times daily, with food.

Common side effects of Viracept include diarrhea and nausea.