Acetaminophen (Paracetamol)
17,260views
00:00 / 00:00
Videos
Notes
Acetaminophen (Paracetamol)
Medicine and surgery
Allergy and immunology
Antihistamines for allergies
Glucocorticoids
Cardiology, cardiac surgery and vascular surgery
Coronary artery disease: Clinical (To be retired)
Heart failure: Clinical (To be retired)
Syncope: Clinical (To be retired)
Hypertension: Clinical (To be retired)
Hypercholesterolemia: Clinical (To be retired)
Peripheral vascular disease: Clinical (To be retired)
Leg ulcers: Clinical (To be retired)
Adrenergic antagonists: Alpha blockers
Adrenergic antagonists: Beta blockers
ACE inhibitors, ARBs and direct renin inhibitors
Thiazide and thiazide-like diuretics
Calcium channel blockers
Lipid-lowering medications: Statins
Lipid-lowering medications: Fibrates
Miscellaneous lipid-lowering medications
Antiplatelet medications
Dermatology and plastic surgery
Hypersensitivity skin reactions: Clinical (To be retired)
Eczematous rashes: Clinical (To be retired)
Papulosquamous skin disorders: Clinical (To be retired)
Alopecia: Clinical (To be retired)
Hypopigmentation skin disorders: Clinical (To be retired)
Benign hyperpigmented skin lesions: Clinical (To be retired)
Skin cancer: Clinical (To be retired)
Endocrinology and ENT (Otolaryngology)
Diabetes mellitus: Clinical (To be retired)
Hyperthyroidism: Clinical (To be retired)
Hypothyroidism and thyroiditis: Clinical (To be retired)
Dizziness and vertigo: Clinical (To be retired)
Hyperthyroidism medications
Hypothyroidism medications
Insulins
Hypoglycemics: Insulin secretagogues
Miscellaneous hypoglycemics
Gastroenterology and general surgery
Gastroesophageal reflux disease (GERD): Clinical (To be retired)
Peptic ulcers and stomach cancer: Clinical (To be retired)
Diarrhea: Clinical (To be retired)
Malabsorption: Clinical (To be retired)
Colorectal cancer: Clinical (To be retired)
Diverticular disease: Clinical (To be retired)
Anal conditions: Clinical (To be retired)
Cirrhosis: Clinical (To be retired)
Breast cancer: Clinical (To be retired)
Laxatives and cathartics
Antidiarrheals
Acid reducing medications
Hematology and oncology
Anemia: Clinical (To be retired)
Anticoagulants: Warfarin
Anticoagulants: Direct factor inhibitors
Antiplatelet medications
Infectious diseases
Pneumonia: Clinical (To be retired)
Urinary tract infections: Clinical (To be retired)
Skin and soft tissue infections: Clinical (To be retired)
Protein synthesis inhibitors: Aminoglycosides
Antimetabolites: Sulfonamides and trimethoprim
Miscellaneous cell wall synthesis inhibitors
Protein synthesis inhibitors: Tetracyclines
Cell wall synthesis inhibitors: Penicillins
Miscellaneous protein synthesis inhibitors
Cell wall synthesis inhibitors: Cephalosporins
DNA synthesis inhibitors: Metronidazole
DNA synthesis inhibitors: Fluoroquinolones
Herpesvirus medications
Azoles
Echinocandins
Miscellaneous antifungal medications
Anti-mite and louse medications
Nephrology and urology
Chronic kidney disease: Clinical (To be retired)
Kidney stones: Clinical (To be retired)
Urinary incontinence: Pathology review
ACE inhibitors, ARBs and direct renin inhibitors
PDE5 inhibitors
Adrenergic antagonists: Alpha blockers
Neurology and neurosurgery
Stroke: Clinical (To be retired)
Lower back pain: Clinical (To be retired)
Headaches: Clinical (To be retired)
Migraine medications
Pulmonology and thoracic surgery
Asthma: Clinical (To be retired)
Chronic obstructive pulmonary disease (COPD): Clinical (To be retired)
Lung cancer: Clinical (To be retired)
Antihistamines for allergies
Bronchodilators: Beta 2-agonists and muscarinic antagonists
Bronchodilators: Leukotriene antagonists and methylxanthines
Pulmonary corticosteroids and mast cell inhibitors
Rheumatology and orthopedic surgery
Joint pain: Clinical (To be retired)
Rheumatoid arthritis: Clinical (To be retired)
Lower back pain: Clinical (To be retired)
Anatomy clinical correlates: Clavicle and shoulder
Anatomy clinical correlates: Arm, elbow and forearm
Anatomy clinical correlates: Wrist and hand
Anatomy clinical correlates: Median, ulnar and radial nerves
Anatomy clinical correlates: Bones, joints and muscles of the back
Anatomy clinical correlates: Hip, gluteal region and thigh
Anatomy clinical correlates: Knee
Anatomy clinical correlates: Leg and ankle
Anatomy clinical correlates: Foot
Acetaminophen (Paracetamol)
Non-steroidal anti-inflammatory drugs
Glucocorticoids
Opioid agonists, mixed agonist-antagonists and partial agonists
Antigout medications
Osteoporosis medications
Assessments
Acetaminophen (Paracetamol)
Flashcards
0 / 14 complete
Flashcards
Acetaminophen (Paracetamol)
of complete
Memory Anchors and Partner Content
External References
First Aid
2022
2021
2020
2019
2018
2017
2016
Acetaminophen p. 498
vs aspirin for pediatric patients p. 498
free radical injury and p. 213
hepatic necrosis from p. 250
for osteoarthritis p. 476
tension headaches p. 536
toxicity effects p. 498
toxicity treatment for p. 249
Glutathione p. 81
acetaminophen and p. 498
External Links
Transcript
Contributors
Filip Vasiljević, MD
Elizabeth Nixon-Shapiro, MSMI, CMI
Kara Lukasiewicz, PhD, MScBMC
Marisa Pedron
Justin Ling, MD, MSAcetaminophen, also known as paracetamol, is mainly used to treat pain and fever. These conditions are related to an increased production of pro-inflammatory chemicals called prostaglandins.
Now, acetaminophen works by decreasing the production of prostaglandins, thereby relieving pain, and reducing fever.
In order to understand how acetaminophen works, first we need to talk briefly about inflammation, which is the body’s response to a harmful stimulus, such as infection or injury.
So, during inflammation, your immune cells use an enzyme called phospholipase A2 to take membrane phospholipids and make a 20 carbon polyunsaturated fatty acid, called arachidonic acid.
Arachidonic acid is a substrate for an enzyme called cyclooxygenase or COX.
The enzyme cyclooxygenase exists in two different isoforms: COX-1 and COX-2.
COX-1 is a constitutive enzyme, meaning that it’s always active, while on the other hand, COX-2 is an inducible enzyme, meaning that it must be turned on to function. This is usually triggered by immune cells and vascular endothelial cells during inflammation.
Both enzymes produce prostaglandin E2 (PGE2) and prostacyclin (PGI2), which cause vasodilation and attract different immune cells to the area.
They also act on neurons that detect pain, called nociceptors, and make them more sensitive to stimuli by lowering their threshold for activation.
Finally, they stimulate the hypothalamus to increase the body temperature, causing fever.
Prostaglandin E2 also has other effects like causing uterine contractions, decreasing the secretion of acid, and increasing the production of protective mucus in the stomach.
Alright, now let’s focus on acetaminophen. Acetaminophen is administered orally, rectally, or intravenously; and it works by reversibly inhibiting COX in the central nervous system, thereby decreasing production of the prostaglandins that cause fever and pain.
Summary
Acetaminophen (Paracetamol) is a medication used to relieve pain and reduce fever. It is usually taken orally, but can also be given intravenously. Acetaminophen is one of the most common medications used and is generally considered safe when taken as directed. However, acetaminophen can cause serious liver damage if too much is taken or if it is taken with certain other medications such as pexidartinib.
Sources
- "Katzung & Trevor's Pharmacology Examination and Board Review,12th Edition" McGraw-Hill Education / Medical (2018)
- "Rang and Dale's Pharmacology" Elsevier (2019)
- "Goodman and Gilman's The Pharmacological Basis of Therapeutics, 13th Edition" McGraw-Hill Education / Medical (2017)
- "Kinetics and metabolism of paracetamol and phenacetin." British Journal of Clinical Pharmacology (1980)
- "Acetaminophen poisoning and toxicity" Pediatrics (1975)
- "Acetaminophen Toxicity" New England Journal of Medicine (1988)
- "What is the most appropriate dose of N-acetylcysteine after massive acetaminophen overdose?" Clin Toxicol (Phila) (2019)
Copyright © 2023 Elsevier, except certain content provided by third parties
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.
