It is useful in the relief of headache and muscle and joint aches. effective in reducing fever, inflammation, and swelling .

Acetylsalicylic Acid, also known by trade name Aspirin, is an acetyl derivative of salicylic acid that is a white, crystalline, weakly acidic substance, with melting point 137°C. It is useful in the relief of headache and muscle and joint aches. Aspirin is also effective in reducing fever, inflammation, and swelling and thus has been used for treatment of rheumatoid arthritis, rheumatic fever, and mild infection.

 Large doses cause acid-base imbalance and respiratory disturbances and can be fatal, especially in children. Acetaminophen (known by trade name Tylenol), which does not cause gastric irritation but does lower fever and relieve pain, is often substituted for Aspirin.

Acetylsalicylic Acid is used in analgesics, anti-inflammatories, antipyretics, anticoagulants and anti-rheumatics. It is also used as an additive in food, animal feed, drug and cosmetic.