acetaminophen(redirected from Tylenol 8 Hour)
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acetaminophen(əsēt'əmĭn`əfĭn), an analgesicanalgesic
, any of a diverse group of drugs used to relieve pain. Analgesic drugs include the nonsteroidal anti-inflammatory drugs (NSAIDs) such as the salicylates, acetaminophen, narcotic drugs such as morphine, and synthetic drugs with morphinelike action such as meperidine
..... Click the link for more information. and fever-reducing medicine. It is an active ingredient in many over-the-counter medicines, including Tylenol and Midol. Introduced in the early 1900s, acetaminophen is a coal tar derivative that acts by interfering with the synthesis of prostaglandinsprostaglandin
, any of a group of about a dozen compounds synthesized from fatty acids in mammals as well as in lower animals. Prostaglandins are highly potent substances that are not stored but are produced as needed by cell membranes in virtually every body tissue.
..... Click the link for more information. and other substances necessary for the transmission of pain impulses. Although its action is similar to that of aspirinaspirin,
acetyl derivative of salicylic acid (see salicylate) that is used to lower fever, relieve pain, reduce inflammation, and thin the blood. Common conditions treated with aspirin include headache, muscle and joint pain, and the inflammation caused by rheumatic fever and
..... Click the link for more information. , it lacks aspirin's anti-inflammatory and blood-thinning effects, is less irritating to the stomach, and can be used by people who are allergic to aspirin. Heavy use, however, has been linked to an increased incidence of liver failure, especially in heavy drinkers of alcoholic beverages and in those who are not eating enough, and overdose, especially in children, can be fatal.
C8H9O2N Large monoclinic prisms with a melting point of 169-170°C; soluble in organic solvents such as methanol and ethanol; used in the manufacture of azo dyes and photographic chemicals, and as an analgesic and antipyretic.