Acetylsalicylic acid belongs to the group of medications called analgesics (pain relievers), antipyretics (fever reducers), anti-inflammatories (inflammation reducers), and platelet aggregation inhibitors (anticlotting agents). Acetylsalicylic acid is used to relieve pain, fever, and inflammation in various conditions such as lower back and neck pain, the flu, common cold, burns, menstrual pain, headache, migraines, osteoarthritis, rheumatoid arthritis, sprains and strains, nerve pain, toothache, muscle pain, bursitis (inflammation of a bursa, a fluid-filled sac located around joints and near the bones), and following surgical and dental procedures. ASA is also used for rheumatic fever in combination with other medications.