The systematic review included observational studies in which patients aged > 18 years, received oral paracetamol at the standard therapeutic dose vs. non-use and the study investigated one or more adverse effects reported. The main outcomes investigated were all-cause mortality, cardiovascular AEs (specifically incidence of myocardial infarction, cerebrovascular accidents and hypertension), gastrointestinal (GI) AEs (specifically incidence of GI bleeding) and renal AEs (specifically reductions in estimated glomerular filtration rate (eGFR), increases in serum creatinine concentration and the need for renal replacement therapy).
The authors highlight several limitations of this systematic review (such as the low number of studies and level of evidence, and people who need long term paracetamol often have multiple medical problems that need other analgesics and drugs), but conclude that given its high usage and availability as an over-the-counter analgesic, a systematic review of paracetamol’s efficacy and tolerability in individual conditions is warranted.