Nonprescription Analgesic Anti-inflammatory Drugs: Efficacy and Safety

Abstract

In the face of widening demand and increased use of nonprescription drugs, there has been increasing attention focused on the efficacy and safety of over-the-counter (OTC) analgesic anti-inflammatory medicines and risks attending their use. The approved dose varies from country to country, but worldwide the major compounds are paracetamol (acetaminophen), aspirin, ibuprofen, diclofenac, and naproxen: these are the focus of the present review; other less widely used or combination medications are not evaluated. The efficacy and safety of each drug is reviewed: what emerges is that, used as recommended at purchase, all of these compounds are effective and safe. Risk/benefit considerations should not govern the choice of compound. However, once sold, they may be misused in higher doses, and for longer durations than recommended, and risks increase, especially if used in combination with similar prescribed compounds that increase the effective dose. In these circumstances, other risk factors also apply, including the user’s age, gender, comorbid illnesses, and co-use of other medications. The adverse events (AEs), seen when OTC compounds are used long term or in higher-than-recommended doses, cannot validly be used to estimate the risks attending correct OTC use, but many observational studies fail to distinguish between AEs associated with prescription and OTC uses. The small number of studies which have evaluated risks associated with excessive use of drugs purchased OTC finds a small but statistically significant increase in the same AEs that are known to be associated with their prescription use. Correct use of OTC compounds is the key to safety.