High-risk use of over-the-counter non-steroidal anti-inflammatory drugs: a population-based cross-sectional study.

Background: The use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with serious adverse drug events (ADEs).

Aim: To determine the prevalence of over-the-counter (OTC) NSAID use in the general population and in patients with a high risk of developing a serious NSAID-related ADE.

Design And Setting: Cross-sectional study in four general practices in the Netherlands.

Method: Two patient samples were selected: a random sample of adults (general population sample); and adult patients with a high risk of developing a serious ADE in case of NSAID use (high-risk sample). All included patients were sent a questionnaire regarding their use of OTC NSAIDs in the 4 weeks prior to participation.

Results: In the general population sample, 118 of 456 (26%) invited patients completed the questionnaire. Of these, 35 (30%) had used an OTC NSAID. In the high-risk sample, 264 of 713 (37%) invited patients completed the questionnaire, and of these high-risk patients 33 (13%) had used an OTC NSAID. Over 20% of OTC NSAID users in the general population sample and over 30% in the high-risk sample had used the OTC NSAID for >7 days. OTC NSAIDs were used in a dosage exceeding the recommended daily maximum by 9% and 3% of OTC NSAID users in the general population and the high-risk sample respectively.

Conclusion: OTC NSAIDs are used by almost one-third of the general population. In the high-risk patients selected, one in eight patients used an OTC NSAID. Continued efforts by health authorities and healthcare professionals to inform patients of the risks of these drugs are warranted.