- Its mechanism of action is not clearly established.
- Kit B given at subcentre is Paracetamol
- It appears that paracetamol inhibits prostaglandin biosynthesis in the central nervous system but not (or hardly) in the peripheral tissues.
- In any case, paracetamol only has minimal anti-inflammatory action compared to non-steroidal anti-inflammatory agents.
- Bioavailability is significantly lower when the drug is administered rectally.
|Bioavailability||Plasma half-life||Plasma half-life||Active metabolites||Elimination|
|constant||80%||40 to 60 minutes||2 to 3 hours||none||predominantly extrarenal|
|Indication||Administration||Initial loading dose||Maintenance dose|
|pains of all kinds||oral||500 mg||4 to 6 hours||250-1000 mg||4 to 6 hours|
- More than 7.5 gm(around 15 tablets)- minimal toxicity
- If >15 gm (30 tablets)- severe toxicity
- In adult- toxic dose is 150 mg/kg
- In children, toxic dose is 200 mg/kg
- In presence of chronic disease or malnutrition, even 2gm of paracetamol can be a toxic dose
- Paracetamol has good analgesic and antipyretic properties.
- It is suitable for the treatment of pains of all kinds (headaches, dental pain, postoperative pain, pain in connection with colds, post-traumatic muscle pain).
- Migraine headaches, dysmenorrhea and joint pain can also be influenced advantageously.
- In cancer patients, paracetamol is used for mild pain or it can be administered in combination with opioids (e.g. codeine).
- Paracetamol has been compared to many other analgesics and is considered approximately equipotent to aspirin (acetylsalicylic acid) .
- Paracetamol is well suited for use in children.
- It represents a preferred alternative when aspirin (acetylsalicylic acid) is contraindicated (e.g. because of a history of ulcer or viral infection in the child).
- Blood dyscrasia (e.g. thrombocytopenia), methaemoglobinemia, and hemolytic anemia are very rare.
- A minority of the subjects with so-called aspirin intolerance responds to paracetamol with bronchospasms.
- An adverse cutaneous reaction to an ingested drug with characteristic clinical features is fixed drug eruption.
- Nephropathy, like drug combinations containing phenacetin.
- Sterile pyuria
- When metabolized in the liver, small amounts of an intensely active metabolite, which is normally immediately inactivated by glutathione, are produced.
- An overdose causes a glutathione deficiency; the reactive metabolite may then cause hepatocellular damage and necrosis leading to acute liver failure.
- Toxic effects have been observed in adults treated with doses of more than 10 g (20 tablets).
- However, if there is a pre-existing liver insufficiency, paracetamol can be hepatotoxic even in small amounts.
- Paracetamol poisoning can cause metabolic acidosis
- Vomiting, pain in abdomen, jaundice and encephalopathy.
- History of attempt to commit suicide.
- The antidote acetylcysteine (e.g. fluimucil) must be administered within 8 to 10 hours when there is intoxication: i.v. infusion of 150 mg/kg in 15 minutes, then 50 mg/kg for 4 hours, and then 100 mg/kg for 16 hours in a 5% glucose solution.
- PCM Poisoning:
- 150mg/kg in 200 ml 5% dextrose over 15 min
- 50mg/kg in 500 ml 5% dextrose over next 4 hours
- 100mg/kg in 1 L 5% dextrose over ensuing 16 hours
- Total dose : 300mg/kg over 20.25 hrs
- Paracetamol poisoning produces Metabolic acidosis
- Vesiculobullous lesion healed with hyperpigmentation on the glans soon after taking tablet paracetamol for fever suggest Fixed drug eruption
- In cases of moderate to severe poisoning of paracetamol, N-acetyl cysteine (mucomyst) should be given orally within 24 hours of overdose to prevent hepatic damage.
- Paracetamol is one of the safest NSAIDs produces very little GI toxicity and can be administered in patients intolerant to other NSAIDs.
- Kit B given at subcentre is Paracetamol
- Sterile pyuria may occur due to Paracetamol
- A patient presented with vomiting, pain in abdomen, jaundice and encephalopathy. There is a history of attempt to commit suicide. Poisoning suspected is Paracetamol
Don't Forget to Solve all the previous Year Question asked on Paracetamol