While researchers suggest patients who have a long-term prescription for the painkiller, should opt for the lowest effective dose for the shortest possible time.
The University of Edinburgh study is the first large randomized clinical trial to address this question and complements earlier work in observational studies.
In the latest 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 for two weeks. All patients received both treatments, with the order randomized and blinded.
Those prescribed paracetamol saw a significant increase in their blood pressure, compared with those taking the placebo.
This rise was similar to that seen with NSAIDs and might be expected to increase the risk of heart disease or stroke by around 20 percent.
Lead Investigator Dr. Iain MacIntyre, Consultant in Clinical Pharmacology and Nephrology at NHS Lothian, 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”.
This study clearly shows that doctors and patients together should consider the risks versus the benefits of long-term paracetamol prescription, especially in patients at risk of cardiovascular disease.
Researchers also recommend that clinicians start with a low dose of paracetamol, and increase the dose in stages, going no higher than needed to control pain.
Given the substantial rise in blood pressure seen in some of our patients, there may be a benefit for clinicians to keep a closer eye on blood pressure in people with high blood pressure who newly start paracetamol for chronic pain.
Source: Medindia