No well-stocked household medicine cabinet is complete without paracetamol. And this attributes to an estimated 100 million pills of the pain reliever Thai people take per year, according to figures from the Government Pharmaceutical Organization. “Thais consume a considerable amount of paracetamol,” commented hepatology specialist Dr Thawat Mongkolporn. “Especially if compared to other countries, Thailand is very likely to take more. Although paracetamol is available over-the-counter everywhere, Thai people have less know-how when it comes to medicine usage.”
People not just in Thailand but around the world rely on paracetamol — also referred to as acetaminophen in the United States, Canada and Japan — as if it was the elixir of life. Whether it’s a headache, fever, cramp or even a hangover cure in the morning, we have always been told and made to believe that two tablets of paracetamol every four hours can fix those problems.
Due to the overconsumption and misuse of paracetamol among Thais, the Food and Drug Administration (FDA) has recently raised concerns over the purchase and prescription of the pain relief among consumers and medical practitioners, alike. According to deputy secretary-general of the FDA Prapon Angtrakul, there have been several reported cases of paracetamol toxicity — a consequence of unintentional drug overdose where ignorance about dosage is mainly to blame.
“Some of the major reasons behind paracetamol overdose are patients receiving the medicinal components from several different sources and wrong dosage based on body weight,” he noted.
In Thailand, paracetamol is available in various trade names, among the most popular ones being Tylenol, Sara and Panadol.
Paracetamol can also be found in such combination drugs as Tiffy and Decolgen, which is mostly used as a cure for several complaints including pain, fever, as well as allergies.
The FDA’s focus is on paracetamol tablets, both 325mg and 500mg. For the medication to take full effect, people have usually been advised to take two tablets every four hours. But according to Dr Thawat, there is actually no fixed dosage when it comes to using the pain killer.
“Most of us understand that two tablets of 500mg paracetamol is to be taken every four hours when we get a fever or experience pain. But such a dosage is not necessarily correct,” the specialist explained. “Paracetamol dosage should be adjusted on a case-by-case basis, based on a person’s weight. And the concept of personalised medicine should be applied here too even though paracetamol is a common medication.”
To work out the correct dosage of paracetamol, according to the hepatologist, simply multiply the body weight by 10, and the result is the amount in milligrammes of paracetamol a person should take each time. For example, if your body weight is 50kg, the right dose of paracetamol is 500mg. This means you are only required to take one tablet of 500mg paracetamol for each dose. If you, however, weigh 65kg, you may take two tablets of the 325mg version per dose which is equivalent to 650mg of paracetamol.
Apart from body weight, a person’s drinking habit should also be taken into account when it comes to working out the right paracetamol dosage, advised the hepatologist.
In a healthy person, the process of paracetamol elimination takes place in the liver where the medicinal component is conjugated and excreted through urine. In the conjugation mechanism, a substance called glucoronide is required as part of the excretion of toxins and drugs. So in the case of people who drink a lot of alcohol, the body already uses glucoronide to rid alcohol and subsequently the body’s ability to purge paracetamol might not be as good as the non-drinkers.
“Even the right dosage of paracetamol based on body weight can become toxic for drinkers because the process of wiping out paracetamol cannot function in full,” noted Dr Thawat, adding that in any cases, the maximum amount of paracetamol intake in a 24-hour period should not exceed 4,000mg, equivalent to eight tablets of 500mg each. And the drug should be taken every six hours — instead of four — to prevent overdose.
Excessive use of paracetamol is likely to cause liver injury. People with paracetamol toxicity may develop no symptoms at all in the first 24 hours following overdose. Others may initially have non-specific symptoms such as abdominal pain, nausea or breathing difficulty. In some serious cases, nonetheless, when paracetamol overload leads to liver inflammation followed by liver failure, patients may develop jaundice.
In relatively healthy people, however, Dr Thawat said that the excess amount of drug will be excreted through urine. But if this process fails, doctors might consider administering medication to help the body wash out paracetamol.
So to prevent paracetamol overdose among Thai consumers, the FDA is considering fixing medicine labels. Combination drugs with a paracetamol component must state clearly it contains paracetamol to avoid consuming the same medicine from several sources. Also, other names such as acetaminophen should not be used on product labels to avoid confusion.
“Consumers are encouraged to read medicine labels carefully and ask pharmacists about certain drugs they are going to take to make sure there is no duplication with regard to the medicine component,” said the FDA.
Registered pharmacist Sittichai Pornchaichanpen said that Thai consumers’ misbelief in terms of paracetamol dosage is primarily caused by unclear and inadequate instructions on the medicine labels. And given that paracetamol is a very standard medicine with which most people are familiar, both consumers and medical practitioners are therefore quite confident the sick know how to take it safely.
“As a pharmacist, I have to admit that many times I feel there is no need to explain to customers about the correct dosage when selling paracetamol and thus fail to provide them with instructions, especially in case of adult clients,” said the 47-year-old, who has operated his own pharmacy in Muang District of Chanthaburi province for more than two decades.
According to Sittichai, his network of pharmacists has become much more careful after the FDA addressed this issue. Personally, he believes that apart from raising awareness among druggists nationwide and revising medicine labels, Thai people should actually be encouraged to take the 325mg version of paracetamol instead of 500mg, which is also in line with the FDA’s plan.
“I once conducted my own small survey on several brands of paracetamol available in the market and found that half of the products I examined had no dosage-related instruction on the labels. On some product labels, however, the instructions are printed too small, so much so I think people may probably need a magnifying glass to read them.
So to tackle and change people’s misunderstanding about this common household medicine, providing them with the right knowledge is key.”
Dr Thawat could not agree more with the FDA’s proposal to handle paracetamol overdose.
He strongly believes that not just doctors and pharmacists but also consumers in general should be more vigilant when it comes to prescribing and taking the drug.
“When you are to take paracetamol, ask yourself if it is necessary,” recommended Dr Thawat.
