Aleve does not contain aspirin, according to Drugs.com. Naproxen is the active ingredient in Aleve, which is a nonsteroidal anti-inflammatory medication that relieves pain and inflammation by reducing the levels of certain hormones in the body.
Doctors recommend Aleve for treating minor pain from arthritis, back and muscular aches, headache, and menstrual cramps, notes Drugs.com. Aleve also treats pain caused by the common cold and toothache and works as a temporary fever reducer. Common side effects of Aleve include stomach pain, itching skin, indigestion and bruising. The typical dose of Aleve in adults and children over 12 years of age is one tablet or capsule every eight to 12 hours.