Acetylsalicylic acid, the active ingredient of this medicine, belongs to a group of drugs known as non-steroidal anti-inflammatory drugs (NSAIDs). It relieves pain and reduces fever. This medicine is used for the symptomatic relief of occasional mild or moderate pain, such as headaches, dental pain, menstrual pain, muscle pain (contractures) or back pain (lumbago) and feverish conditions in adults and adolescents over 16 years of age. You should consult a doctor if it gets worse or if it does not improve after 5 days for pain or 3 days for fever.