Advil is an anti-inflammatory commonly used for relieving headaches, toothaches, back pain, menstrual cramps and arthritis, states Drugs.com. The active ingredient in Advil is ibuprofen, which reduces the amount of hormones that cause inflammation and pain.
The typical adult dose of Advil is 200 to 400 milligrams, states MedicineNet. Side effects include rash, nausea, abdominal pain, diarrhea and heartburn. For long-time users and those with heart disease, Advil can lead to heart attack and stroke, states Drugs.com. It can also cause intestinal or stomach bleeding, which is often fatal. Pregnant women who take Advil during the last three months of pregnancy may cause damage to the unborn child.