Questions on Medicines, Alcohol, and Illicit Drug Interactions in the Finnish AddictionLink Online Service: A Descriptive Analysis

Aims: To explore which drugs and intoxicants people most commonly seek information about from the Finnish AddictionLink online information service and to describe the types of the drug interaction questions submitted, the most frequently mentioned substances in the questions and the background characteristics of the questioners. Methods: The study was conducted using data from the Finnish AddictionLink online information service. Medication-related questions submitted between 2011 and 2023 ( n = 1858) were extracted. Interaction-related questions ( n = 242) and the substances mentioned were categorized and analyzed. Background characteristics were described for individuals who submitted drug interaction-related questions ( n = 197) and for those who submitted other medication-related questions ( n = 1070). Results: Most questions concerned interactions between medications and intoxicants, with alcohol being the most frequently mentioned intoxicant, followed by stimulants and cannabis. Antidepressants were the most frequently mentioned drug class, followed by opioids, cardiovascular drugs, and benzodiazepines. Participants aged 13–25 years and those aged 46 years or older appeared to submit interaction-related questions more frequently, whereas individuals aged 26–45 were more likely to submit other medication-related questions. Conclusions: Questions concerning the concurrent use of medications with alcohol or illicit substances highlight a clear need for accessible and understandable information on drug–intoxicant interactions. The frequent involvement of antidepressants and other commonly used medications underscores the relevance of these interactions in routine treatment. Increasing awareness among both healthcare professionals and medication users is essential to support safer treatment choices.