Acetaminophen Flashcards
Therapeutic classification
o Non-opioid analgesic, antipyretic
Pharmacologic Classification
o Para-aminophenol derivative
Pregnancy Category
B
Mechanism of Action
o Inhibits COX in CNS
o May inhibit chemical mediators of pain
o Direct action on the heat-regulating center of the hypothalamus to produce peripheral vasodilation, sweating and dissipation of heat.
Indications
o Mild to moderate pain o Osteoarthritis of hip or knee o Dysmenorrhea o Dental procedures o Headache and myalgia o Fevers
Contraindictions
o Allergy to acetaminophen
Precautions
o Anemia o G6PD defieciency o Hepatic disease o Rheumatoid or osteoarthritis o Malnutrition o Bone marrow depression o Immunosuppression o Renal impairment
Drug Interactions
o Alcohol increases risk of hepatotoxicity
o Barbiturates, carbamazepine, diphenylhydantoin, isoniazid, rifampin and sulfinpyrazone (additive effect)
o Will decrease lamotrigine levels if the drugs are administered concurrently
o Can increase hypoprothrombinemic effects with warfarin.
o Can increase the risk of bone marrow suppression with zidovudine
o Hepatotoxicity reported with Echinacea
Adverse Effects
o At recommended doses, acetaminophen is well tolerated
Serious Adverse Effects
o Acute hepatic failure o Acute acetaminophen poisoning with symptoms such as anorexia, nausea, diaphoresis or abdominal pain o Chronic use can lead to: • Neutropenia • Pancytopenia • Leukopenia • Thrombocytopenic purpura • Hepatotoxicity in alcoholics • Renal damage
Nursing Responsibilities
o Assess recent drug history
o Assess effectiveness of the medication
o Perform baseline and periodic liver function test (AST and ALT) monitor for signs and symptoms of hepatotoxicity
o Assess alcohol use
Patient/family teaching
o Do not increase the dose or take the drug more frequently
o Seek immediate medical attention if fever lasts more than 3 days
o Do not drink alcohol
o Report any signs of potential liver toxicity
o Keep the drug in a secure location away from small children.
