A systematic review of the effect of paracetamol on blood pressure in hypertensive and non-hypertensive subjects

Aim To review current evidence on the effect of paracetamol on blood pressure (BP), the quality of the previous studies and the validity of the results, and to summarize these findings. Methods A systematic literature review was performed by searching PubMed, the Cochrane library and EMBASE for publications between the years 1963 and 2012. Results We identified three case reports, seven prospective observational trials, six randomized controlled trials, one commentary and two reviews. Some, but not all, of the observational studies, which included over 147000 patients, showed an increased risk of hypertension with paracetamol use. The randomized studies were generally small and the results were inconsistent. Three studies, which included 104 patients, showed an increase of systolic BP by approximate to 4mmHg, two studies, which included 27 patients, reported no change in BP and one study, which included 21 patients, reported a fall in BP although no placebo arm was included for comparison. Conclusions The overall effect of paracetamol on BP is unclear. Given that paracetamol is often suggested as a safer alternative to non-steroidal anti-inflammatory drugs (NSAIDs), it would seem that further prospective evidence is now needed to address the effect of paracetamol on BP. This would be best done with larger studies in relevant cohorts using BP measured by ambulatory BP monitoring as the primary endpoint.