Restriction of non-opioid analgesics sold over-the-counter in Denmark:A national study of impact on poisonings

Self-poisoning with non-opioid analgesics presents a growing challenge to health care providers. We aimed to assess the impact of an 18-year age restriction of OTC sales and a pack size restriction of non-opioid analgesics sold OTC in pharmacies on hospital-treated poisonings and poisoning severity measured using biomarkers.We applied a before and after design using interrupted time series analysis. Data on all poisonings recorded as hospital admissions were obtained during 2002-2015 and biochemical parameters from laboratory databases during 2011-2015, both covering the entire Danish population.The age restriction was followed by a 17% level reduction in admissions for non-opioid analgesic poisoning among young people age 10-17 years (RR 0.830; 95% CI 0.697-0.988; p 0.036). After the pack size restriction, an instant level reduction of 18.5% (RR 0.815; 95% CI 0.729-0.912; p 0.001) was observed for the entire population. A 27% decrease in the number of poisonings with alanine transaminase levels (ALT) ≥ 210 U/L was observed (RR 0.734; 95% CI 0.579-0.931; p = 0.011) followed by 40% decrease in biomarkers indicative of liver failure (RR 0.597; 95% CI 0.421-0.847; p = 0.004). We also observed similar reductions for other poisonings such as psychotropics.Although declines in poisonings were observed after implementation of means restrictive measures, a causal link cannot be inferred.Age and pack size restriction were assiociated with a reduction in the numbers of poisonings. This was also observed for pharmaceutical poisonings in general, which might suggest a non-specific or spill-over effect.