Aleve, the fast acting pain reliever and fever reducer, has the strength to stop tough pain including backache, headache, muscle cramps, toothache, menstrual cramps and minor arthritis pain all day long. That is why it is known for its tag line "All Day Strong, All Day Long". Caplets make this medicine especially easy to swallow. Active ingredient (in each caplet): naproxen sodium 220 mg.