NCLEX Review: Acetaminophen (Analgesic, Antipyretic, NOT an NSAID) – Mechanism of Action, Uses, Side effects, Nursing considerations, and Antidote
Hi everyone this is ryan from rpnt.ca and today we’re going to be talking about the drug acetaminophen also known as paracetamol or by the brand name tylenol you can use the timestamps in the video description to jump ahead it’s surprising that acetaminophen’s exact mechanism of action is still not fully understood even though it is a very common over-the-counter
Medication it is thought that acetaminophen works very similarly to non-steroidal anti-inflammatory drugs or nsaids like ibuprofen and celecoxib nsaids reduce inflammation and fever and reduce pain but a major distinction between acetaminophen and nsaids is that acetaminophen does not exert any anti-inflammatory effects and is therefore not an nsaid in our body
We have enzymes called cyclooxygenase or cox for short that are responsible for producing prostaglandins prostaglandins have many different effects throughout the body just some of which include inflammation and fever which aid in the healing process but may cause pain prostaglandins can also decrease the body’s pain threshold affect blood clotting and so much
More so it is thought that acetaminophen works by inhibiting cyclooxygenase which in turn inhibits the production of these prostaglandins and if we have fewer of these prostaglandins we should have less inflammation less fever and less pain again always remember that acetaminophen does not actually reduce inflammation this is because acetaminophen is thought
To act primarily in the central nervous system which consists of the brain and spinal cord and not in the peripheral tissues throughout the body so acetaminophen can increase the pain threshold by inhibiting prostaglandins in the central nervous system and can reduce fever by acting in the hypothalamus which also is part of the central nervous system but
Again it does not act in the peripheral tissues like an nsaid so there is no reduction of inflammation throughout the body so one last review of how it works acetaminophen is thought to inhibit cyclooxygenase enzymes which inhibits the production of prostaglandins in the central nervous system decreasing pain and fever so acetaminophen is used as an analgesic
For the treatment of mild to moderate aches and pains like headaches dental pains arthritis pains and more it is also used as an antipyretic for the treatment of fever side effects are not very common with acetaminophen at normal doses however in higher doses hepatotoxicity may occur which is damage to the liver usually caused by drugs acetaminophen-induced
Hepatotoxicity is more likely to occur in patients who already have some comorbidities like liver failure or alcohol abuse it may take a couple of days to see signs and symptoms of hepatotoxicity unless there is a major overdose of acetaminophen hepatotoxicity may present as jaundice which is the yellowing of the skin or eyes due to the liver’s inability to
Break down bilirubin you may see right upper quadrant tenderness or pain which is where the liver is you may see elevated liver enzymes like ast and alt in the blood which is an indication of liver cell damage you may see darker urine and much more although acetaminophen helps to lower fever it’s important to recognize that acetaminophen does not actually
Help to treat any underlying cause of the fever so if a fever persists for an extended period of time usually more than three days notify the care provider as a serious infection or illness may be present the recommended maximum daily dosage for acetaminophen is usually four grams or four thousand milligrams per day anything above this could increase the risk
Of hepatotoxicity keep in mind that this 4 gram limit per day applies to all sources of acetaminophen intake there are lots of over-the-counter medications that contain multiple drugs especially cold medications which often contain acetaminophen as one of the components acetaminophen is often administered as an oral tablet of 325 or 500 milligrams but is also
Available in extended release forms liquid forms and as a suppository for rectal use in the event of acetaminophen overdose acetyl cysteine can be used to decrease liver toxicity and that’s about it for the basics of acetaminophen if you have any questions please let me know in the comments or visit rpnt.ca for more help
Transcribed from video
Acetaminophen / Paracetamol (Tylenol) Nursing Drug Card (Simplified) – Pharmacology By Nurse Ryan
