What does acetaminophen do and how does it work? Acetaminophen is a pain reliever and fever reducer. It is thought to work to relieve minor aches and pains by elevating the body’s overall pain threshold so you feel less pain, and lowers your fever by helping your body eliminate excess heat. Find patient medical information for Acetaminophen (Tylenol) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Acetaminophen is found in hundreds of over-the-counter and prescription drugs. It may be the only active ingredient, or it may be combined with other active ingredients. Acetaminophen is sold. Paracetamol, [a] or acetaminophen, [b] is an analgesic and antipyretic agent used to treat fever and mild to moderate pain. [14][15] It is a widely available over-the-counter drug sold generically or under various brand names, including Tylenol and Panadol. Acetaminophen is a popular over-the-counter medication that is commonly used to treat mild to moderate pain from various conditions, including headaches, dental pain, muscle aches, and menstrual cramps, as well as the discomfort associated with colds and sore throats. Learn about the side effects of acetaminophen, from common to rare, for consumers and healthcare professionals. Acetaminophen is an analgesic used to temporarily relieve minor aches and pains. Learn about side effects, drug interactions, dosages, warnings, and more. Acetaminophen is used to relieve mild to moderate pain and to reduce fever. Acetaminophen is in a class of medications called analgesics (pain relievers) and antipyretics (fever reducers). It is not safe to use more than 4 grams (4,000 milligrams) of acetaminophen in one day (24 hours), as this may increase the risk for serious liver problems. For Tylenol® Extra Strength, the maximum dose is 3,000 milligrams per 24 hours. Acetaminophen is used for the short-term relief of minor aches and pains due to colds, flu, headache, backache, arthritis, toothache, muscle pain, and menstruation. It also temporarily reduces fever. Outside of the United States, Canada, and Japan, acetaminophen is called paracetamol.