The number of deaths due to acetaminophen overdoses has declined significantly in the UK since legislation was passed limiting the number of tablets that can be sold, according to a new study published in the peer-reviewed BMJ.
Researchers say deaths from acetaminophen (known as paracetamol in the UK) fell by 43% in England and Wales since the law was enacted 15 years ago. They estimate that 765 lives have been saved since prescriptions for the pain reliever were limited to 32 tablets — and just 16 tablets for over-the-counter sales.
“The effect of the 1998 legislation on pack sizes of paracetamol is likely to reflect the fact that many people who intentionally overdose with paracetamol take what is available in the household, especially if the overdose is impulsive,” wrote Keith Hawton, lead researcher from the University of Oxford Centre for Suicide Research.
The passage of the legislation was, in large part, a reaction to a wave of overdoses, both accidental and intentional, involving the widely used drug.
But the effectiveness of the legislation has come into question in recent years. That prompted the Oxford researchers to investigate the long-term impact it was having on poisoning deaths, especially suicides, and on the number of patients admitted to hospital for liver failure.
Using figures from the Office of National Statistics, researchers found that cases of acetaminophen-related acute liver failure between 1993 and 2009 fell by 61%, although actual transplants did not decrease. Acetaminophen overdoses are a common method of suicide and frequent cause of liver damage.
From 1993 to 1998, before the law was enacted, deaths attributed to acetaminophen poisoning in England and Wales averaged just over 5.000 annually. From 1999 to 2009, the average dropped to 4,773. The cases used in the study excluded products that combined acetaminophen with other medications, although acetaminophen with alcohol was included.
In spite of the apparent success of the law, there continues to be a considerable number of deaths each year due to acetaminophen poisoning. Researchers say that fact alone should encourage health care providers to remain vigilant, and not become complacent.
“We are extremely pleased that this measure has had such benefits, but think that more needs to be done to reduce the toll of deaths from this cause,” said Hawton.
Among the additional measures he suggests includes stronger enforcement of the law, further reduction in pack sizes, and possibly a reduction in acetaminophen content of tablets.
Acetaminophen has increasingly come under fire on both side of the Atlantic because dosages not much in excess of recommended levels can lead to acute liver failure.
Acetaminophen is found in hundreds of over the counter medications including Tylenol, Excedrin, Nyquil and Sudafed, and is often combined with opioids to make stronger painkillers such as Vicodin and Percocet. Acetaminophen overdoses account for over half of all cases of acute liver failure in the U.S
In 2011, the FDA cut the maximum acetaminophen dosage in multi-ingredient products to 325 mg. per tablet or capsule, because of the liver-failure risk. However, acetaminophen-only tablets can still be 500 mg. and there is no limit on bottle size in the U.S.
Over 50 million people in the U.S. use acetaminophen each week to treat pain and reduce fever.