Neuropsychiatric reactions to nonsteroidal anti-inflammatory drugs (NSAIDs). The New Zealand experience.

The New Zealand Medicines Adverse Reactions Committee has been monitoring reports of adverse drug reactions (ADRs) since 1965. We wished to determine the numbers of voluntary reports of different types of ADR to all nonsteroidal anti-inflammatory drugs (NSAIDs) over a long time period and relate these to age. As the elderly are known to suffer from neuropsychiatric adverse effects of many drugs, we investigated neuropsychiatric reactions to NSAIDs to determine whether these were more commonly reported in the elderly. We counted all reported ADRs suspected to be associated with NSAIDs as well as selected types of ADRs reported from 1970 to 1989. These were divided into 5-year periods and 10-year age groupings. In each consecutive 5-year period there was a progressive increase in the numbers of all ADRs reported for all NSAIDs. This was particularly marked above 50 years of age, but the numbers were reduced above 80 years. Reports for females accounted for about two-thirds of all reactions. Not unexpectedly, alimentary and dermatological ADRs accounted for most reactions and were more common in the group above 50 years. Overall, neuropsychiatric reactions were the third most common ADR type reported. Their numbers increased with age and peaked in the 50 to 59 age group, with a sharp decline after 69 years. This age distribution paralleled that for all ADRs to NSAIDs. Although neuropsychiatric reactions to NSAIDs were reported in all age groups, they were not reported more commonly in the elderly. This study suggests that neuropsychiatric reactions to NSAIDs may be more frequent than is commonly believed.