Side effects of OTC medicines: Paracetamol overdose can lead to liver failure

Paracetamol is one of the most misused OTC drugs. Read to know the recommended doses of paracetamol and possible side effects.

We usually rely on home remedies and over the counter (OTC) drugs for common conditions like a common cold, seasonal flu, cough, fever, headache or muscle pain. These drugs can give you immediate relief, sometimes they can cause adverse effects, which could be side effects, drug-drug interactions, food-drug interactions, or allergic reactions. OTC medicines can be dangerous if you don't follow recommended doses, directions, and warnings. Paracetamol, also known as acetaminophen, is one of the most misused OTC drugs.

Paracetamol overdose can cause serious liver damage

Paracetamol is commonly used to treat aches, pain, and fever. It is easily available at all pharmacy stores without a prescription, sold by different brands with different names. This common OTC drug is an effective treatment for mild or moderate pain, such as headaches, toothache or sprains, and fever caused by illnesses such as colds and flu. When taken as directed on the label or leaflet, or as instructed by a health professional, it's safe for most people to take and side effects are rare. But overdoing can lead to liver and kidney damage, which can be fatal in severe cases.

Paracetamol overdose or toxicity is identified as one of the common causes of acute liver failure a life-threatening condition in which your liver suddenly stops working within a matter of days or weeks. It occurs most often in patients who do not have pre-existing liver disease. Paracetamol-linked liver failures are so severe that the patient may need a transplant.

A study, published in Scientific Reports in 2017, looked at the impact of this common painkiller on liver cells in human and mouse tissue. The researchers from Edinburgh University found that the drug can damage the liver by harming vital structural connections between adjacent cells in the organ. This type of cell damage is also known to occur in liver conditions including hepatitis, cirrhosis and cancer.

Know the recommended paracetamol doses

The recommended dose of paracetamol is one or two 500mg tablets every 4-6 hours for adults. This means you shouldn't take more than 4g (eight 500mg tablets) in the space of 24 hours.

Children under 16 need to take a lower dose, depending on their age or weight check the packet or leaflet, or ask a pharmacist or doctor for advice.

For very young children, paracetamol liquid is given using a measuring spoon or an oral syringe.

Paracetamol very rarely causes side effects if taken at the right dosage. In rare cases, some people may experience a serious allergic reaction (anaphylaxis) to the drug. If you've had an allergic reaction to it in the past, don't take it again.

It may not be safe to take paracetamol if you're taking the blood-thinner warfarin (it can increase the risk of bleeding), and medicines to treat epilepsy and tuberculosis (TB). Also, people who have liver or kidney problems, have problems with alcohol, such as long-term alcohol misuse, and are very underweight should always consult a doctor before taking paracetamol.

For safety, it is best to talk to your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.