Study says long-term use of paracetamol raises blood pressure in hypertensive patients

A new study has found that long-term paracetamol use raises blood pressure in people with hypertension, which could increase the risk of heart disease and strokes.

According to the University of Edinburgh researchers, it has been assumed that acetaminophen — a generic name for paracetamol — was a completely safe drug to use in patients with the condition, compared to another class of painkillers called non-steroidal anti-inflammatory drugs (NSAIDs), which are known to increase blood pressure and risk of heart disease.

They, therefore, decided to carry out the study, published on Monday, to identify the effects of regular acetaminophen dosing on blood pressure in individuals with hypertension.

In the study, 110 patients with a history of high blood pressure were prescribed one gram of paracetamol four times a day – a routinely prescribed dose in patients with chronic pain – or a matched placebo (fake pill) for two weeks. All patients received both treatments, with the order randomised and blinded.

Those prescribed with paracetamol saw a significant increase in their blood pressure, compared with those taking the placebo.

The research team said the findings should lead to a review of long-term paracetamol prescriptions to patients – particularly those with high blood pressure, or those at particular risk of heart disease or stroke.

Iain MacIntyre, lead investigator and consultant in clinical pharmacology and nephrology, said: “This is not about short-term use of paracetamol for headaches or fever, which is, of course, fine – but it does indicate a newly discovered risk for people who take it regularly over the longer term, usually for chronic pain.”

James Dear, personal chair of clinical pharmacology at the University of Edinburgh, said the study clearly shows that paracetamol increases blood pressure, one of the most important risk factors for heart attacks and strokes.

“Doctors and patients together should consider the risks versus the benefits of long-term paracetamol prescription, especially in patients at risk of cardiovascular disease,” he said.