Paracetamol common source of accidental overdoses

Researchers are urging doctors and pharmacists to talk to patients about how to take paracetamol correctly, because of its high potential for toxicity.

Widely available and commonly used, paracetamol is perceived as a safe drug, but it is a leading cause of preventable acute liver failure in Aotearoa, New Zealand and globally.

Despite its availability, little has been known about the New Zealand public’s understanding of its safe use, so researchers from Waipapa Taumata Rau, University of Auckland studied New Zealanders’ attitudes to paracetamol and practices. See New Zealand Journal of Primary Health Care.

“People think it's safe, which it is if you take it at the right dose; but, because of the way it's broken down by the body, when you take more than the recommended dose, the liver gets overwhelmed and can be damaged,” says Dr Samantha Marsh, a senior research fellow in the Department of General Practice and Primary Care at the University of Auckland.

The study revealed significant gaps in understanding, particularly in identifying paracetamol-containing products and adhering to dosing guidelines.

The recommended dosage is two tablets every four hours up to a limit of eight tablets per day.

However, misuse is common with a third of New Zealanders commonly taking more than two tablets at once and 11 percent exceeding the daily limit, the study finds.

“People say, ‘I take more than two tablets, because I am a big person,’ but it doesn’t work like that,” Marsh says.

The study was based on an online survey of almost two-thousand people who broadly represented the makeup of the New Zealand population.

Two-thirds of respondents (70 percent) agreed that paracetamol was a very safe drug and almost as many (65 percent) thought that you can buy paracetamol from the supermarket because it is safe.

Many people (32 percent) will ask their doctor for a paracetamol prescription, even when they went for something else.

A similar proportion (27 percent) have asked for a paracetamol prescription then shared it with friends and family.

Another finding was that around half of respondents struggle to identify paracetamol in common cold and flu products, like Lemsip or Coldral, which could mean many more people are taking more paracetamol than they should, but they aren’t even aware of it

Marsh would like to see stickers on the front of such products with a warning – “Do not take with paracetamol” or “contains paracetamol”.

There was strong support for greater regulation.

While most considered it safe, more than half (55 percent) thought there should be restrictions on how much you can buy at once. A third thought there should be restriction on where you can buy it.

Regulation has had mixed success overseas, Marsh says. “There needs to be more research to ascertain what the best way to regulate is,” she says.

A particularly at-risk group is children, according to data from the National Poisons Centre.

• About 60 percent to 65 percent of calls to the New Zealand National Poisons Centre relate to children under five. Paracetamol is the most common substance involved in poisoning in this age group.

• The New Zealand National Poisons Centre receives about 1000 calls a year about paracetamol poisonings. About half of these calls involve children helping themselves to medication.

Marsh says parents need to keep track of how much paracetamol, often as Pamol, they have given their children, for example by writing it down where the other parent can see.

With measles cases on the rise in New Zealand, many parents may reach for paracetamol to ease fever and discomfort.

“It’s important to remember that paracetamol is safe only when used at the correct dose – even a small error can cause harm,” Marsh says.

“When a child is very unwell, it’s easy for tired or stressed parents to lose track of doses, particularly in the middle of the night, so keeping a written record can help prevent harm.”

Two-thirds of people said their doctors and pharmacists had never spoken to them about the dangers of taking too much paracetamol.

There needs to be an education campaign on when and how to take paracetamol, Marsh says.

“When you get paracetamol from either the doctor or a pharmacist, they should always remind you that you must take it according to the package.”

• Paracetamol fact sheet