The major difference between naproxen, the active ingredient in Aleve, and ibuprofen is that the former is not considered safe for use by patients with a history or risk of cardiovascular disease, while the latter is thought to be safer for such patients. Another difference is that naproxen is longer lasting than ibuprofen. Both are types of over-the-counter non-steroidal anti-inflammatory drugs.
WebMD reports that both naproxen and ibuprofen are used to reduce fever and to provide relief for mild aches and pains, including mild toothache, cramps and headaches. These drugs, as well as the other type of non-steroidal anti-inflammatory drug available, aspirin, are also used to treat arthritis and to relieve symptoms of the common cold or flu.
According to the Harvard Medical School Family Health Guide, ibuprofen tends to be a preferred pain reliever because it acts quickly and does not remain in the body too long. Per dose, ibuprofen is less likely to cause stomach or kidney problems. Ibuprofen is sold under the brand names Advil and Motrin IB.
The effects of naproxen last between eight and 12 hours, compared to an equivalent dose of ibuprofen, which lasts from four to eight hours, according to About Health.