In their review, Schifano et al attempted to investigate the published clinical data on OTC misuse, focusing on antihistamines (e.g., diphenhydramine, promethazine, chlorpheniramine, and dimenhydrinate), dextromethorphan (DXM)- and codeine-based cough medicines, and the nasal decongestant pseudoephedrine.

The researchers conducted a systematic literature review using data from Scopus, Web of Science databases, and the related gray literature. After completion of the selection, eligibility, and screening phases, some 92 articles were taken into consideration; case reports, surveys, and retrospective case series analyses were included. The findings were organized according to the specific OTC drug recorded, and the majority of the articles focused on DXM (n = 54) and diphenhydramine (n = 12).

The authors found that, overall, the misuse of OTC drugs is considered more socially acceptable, less stigmatizing, and safer than the intake of illicit substances, also due to their likely lack of detection in standard drug screens. Additionally, many individuals are not aware of the harmful effects associated with misuse of OTC drugs. They also noted that OTC-drugs intake may involve snorting or injecting the crushed tablets' powder to amplify the euphoric effects of a drug or ingesting these molecules for a purpose different from the therapeutic one, which may be the case for DXM- and codeine-based cough mixtures; conversely, loperamide is ingested for self-medicating withdrawal symptoms.

It is important for healthcare providers to be aware that the misuse of OTC drugs is correlated with significant drug interactions, physical and mental health effects, individual variation in responses, and significant socioeconomic impact for the users, their families, and the wider community. The authors concluded that their systematic review revealed that the issues related to misuse of OTC drugs are prevalent and geographically widespread. They also noted that the most vulnerable patient populations included adolescents and young adults, although real prevalence figures remain unknown owing to a lack of appropriate monitoring systems.  

Considering the potential, and at times serious, adverse effects associated with OTC medication misuse, the authors noted, healthcare professionals should be watchful, and ad hoc preventative actions should be designed and implemented to identify and address the issues related to misuse of OTC drugs. The authors recommended that healthcare providers utilize abuse-prevention campaigns, which may provide valuable resources on raising awareness and preventing medicine abuse, such as https://stopmedicineabuse.org/ and https://www.drugabuse.gov/drug-topics/over-counter-medicines.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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