Paracetamol is widely taken for mild to moderate pain relief. (Image: Getty)
Regular use of paracetamol may raise blood pressure, according to research that has prompted fresh questions about long-term painkiller use. The medicine, commonly taken to ease pain and reduce high temperature, is often used for headaches, joint pain and stiffness, toothache, sore throats, and fever linked to colds or flu. For years, paracetamol has generally been regarded as a safer choice for people with high blood pressure than some alternatives, particularly non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen.
But a 2022 study suggested routine paracetamol use can have a noticeable impact on blood pressure. Researchers gave 110 patients with a history of high blood pressure either one gram of paracetamol four times daily — a standard dose often prescribed for chronic pain — or a matched placebo for two weeks. Those taking paracetamol experienced a significant rise in blood pressure compared with the placebo group. Every participant received both treatments, with the order randomised and blinded. Experts said the increase was similar to that seen with NSAIDs and could be expected to raise the risk of heart disease or stroke by about 20%.
The researchers said the results should encourage doctors to reassess long-term paracetamol prescriptions, particularly for patients who already have high blood pressure. The University of Edinburgh study, published in the scientific journal Circulation, was described as the first large randomised clinical trial to examine the issue and added weight to earlier findings from observational research.
Professor James Dear, personal chairman of clinical pharmacology at the University of Edinburgh, said: “This study clearly shows that paracetamol, the world’s most used drug, increases blood pressure, one of the most important risk factors for heart attacks and strokes.
“In summary, we’ve shown that two weeks of treatment with paracetamol increases blood pressure in patients who have hypertension (high blood pressure).”
Lead investigator Dr Iain MacIntyre, consultant in clinical pharmacology and nephrology at NHS Lothian, stressed that the warning does not apply to occasional use. He 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.”
Professor Sir Nilesh Samani, medical director at the British Heart Foundation, which funded the study, said the findings “emphasise why doctors and patients should regularly review whether there is an ongoing need to take any medication” and “always weigh up the benefits and risks.”
“However, if you take paracetamol occasionally to manage an isolated headache or very short bouts of pain, these research findings should not cause unnecessary concern.”
Phil Pyatt, CEO of Blood Pressure UK also said: “Paracetamol is the most commonly taken medicine in the world. People taking soluble versions don’t realise they’re taking on extra sodium, in some cases enough to take you over your maximum for the day, and this research shows that these medicines could lead to life-changing illness. It’s concerning to see that even the regular tablets could raise blood pressure which could have consequences in the long term.
“There is no need to worry about short term use, but patients, doctors and pharmacists should be aware that these medicines that seem harmless could have serious implications in the long term. They should weigh up the risks and benefits and lower the dose if possible and consider whether they are necessary.”
High blood pressure, also known as hypertension, affects around 1.4 billion people worldwide and is a major risk factor for heart disease and stroke. According to the latest figures, around 16 million people in the UK are estimated to have high blood pressure but almost five million of them don’t know they have it.
Rarely, it can cause symptoms such as headaches, blurred vision or chest pain. However, the NHS has stressed that the only way to find out if you have high blood pressure is to get your blood pressure checked.
