• Paracetamol, a common painkiller in households, carries significant risks, especially to liver when not used as recommended.
Paracetamol has been a rescue pill for most people. Almost every household has a strip of this medicine as it is a common over-the-counter painkiller used to treat headaches, muscle aches, and even fever.
But most people often end up popping a paracetamol for the slightest symptom, which should be taken with caution.
Despite its widespread use and perceived safety, paracetamol, also called acetaminophen, carries significant risks, particularly to the liver, when not used as recommended.
Paracetamol works by inhibiting the production of prostaglandins, which are chemicals in the body responsible for inflammation and pain.
Unlike nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or aspirin, paracetamol does not have significant anti-inflammatory properties, making it a more suitable option for those who need pain relief without the risk of stomach irritation.
While paracetamol is a safe drug, consuming more than the recommended dose could lead to liver damage.
The liver is responsible for metabolising paracetamol, breaking it down into various substances, some of which are toxic. Under normal circumstances, the liver can handle these toxins by converting them into harmless substances that are then excreted from the body.
However, when paracetamol is taken in excessive amounts, the liver’s ability to process these toxins is overwhelmed, leading to liver damage.
According to the National Library of Medicine, liver toxicity from paracetamol overdose, whether intentional or non-intentional, is the most common cause of drug-induced liver injury in the United States.
Limit intake to 2 to 3 tablets a day; if needed, take only half a tablet at a time, say experts.
Drugs standard control organisations recommend a daily dose of 4 grams (4,000 mg) of paracetamol for adults. It should not exceed 7 to 10 grams.
This is typically divided into doses of 0.5 to 1 gram (500 to 1,000 mg) every 4 to 6 hours. However, the total daily dose should not exceed 4 grams to avoid the risk of liver damage. In children, doses should not exceed 150 mg per kg of body weight.
Dr Sakshi Singh, Consultant, Internal Medicine, Amrita Hospital, Faridabad, India said that glutathione is a protective substance in the liver that helps neutralise paracetamol. When consumed excessively, this substance gets depleted, leading to liver toxicity.
“Beyond the safe limit, paracetamol becomes detrimental, risking acute liver failure. This toxicity manifests as nausea, vomiting, and abdominal pain, progressing to liver damage and potential failure, if untreated,” Dr Singh said.
The expert advised people against taking repeated doses of this analgesic without medical consultation and supervision.
A study by researchers at the University of Edinburgh found the effects of paracetamol on the liver.
They studied human cells and mouse tissue, and that showed in certain settings, paracetamol can damage the liver by harming vital structural connections between adjacent cells in the organ.
According to Dr Cyriac Abby Philips, who goes by The Liver Doc on X, “In its recommended dose and duration, for specific age groups, paracetamol is the safest medication there is, even for patients with liver disease. It can be prescribed for management of fever as well as pain in persons with chronic liver disease. General physicians please heed.”
However, paracetamol is not the culprit.
Paracetamol has a high bioavailability with almost 80% of the drug being absorbed when taken orally. When taken in very high doses, the compound is converted into toxic metabolite.
At normal doses, the body safely breaks down most paracetamol. But in an overdose, the liver can’t handle it, creating a toxic substance called NAPQI (N-acetyl-p-benzoquinone imine).
Normally, NAPQI is neutralised, but in high doses, it depletes the body’s defences, leading to cell damage, inflammation, and potentially, liver failure.
Dr Shrihari Anikhindi, Consultant Gastroenterologist & Hepatologist at Sir Ganga Ram Hospital, said, the quality of compounds matters not only for good efficacy but also to avoid unwanted side effects.
“One should check the quality as well. If you have to buy paracetamol, to avoid unwanted side effects, use a trusted brand,” Dr Anikhindi said.
Doctors advise taking paracetamol in the recommended doses, and not to excessively consume it to avoid liver damage.