Focus on Over-the-Counter Drugs' Misuse: A Systematic Review on Antihistamines, Cough Medicines, and Decongestants

Abstract

Background: Over the past 20 years or so, the drug misuse scenario has seen the emergence of both prescription-only and over-the-counter (OTC) medications being reported as ingested for recreational purposes. OTC drugs such as antihistamines, cough/cold medications, and decongestants are reportedly the most popular in being diverted and misused.Objective: While the current related knowledge is limited, the aim here was to examine 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.Methods: A systematic literature review was carried out with the help of Scopus, Web of Science databases, and the related gray literature. For data gathering purposes, both the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and PROSPERO guidelines were followed (PROSPERO identification code CRD42020209261).Results: After completion of the selection, eligibility, and screening phases, some 92 articles were here taken into consideration; case reports, surveys, and retrospective case series analyses were included. Findings were organized according to the specific OTC recorded. Most articles focused here on DXM (n = 54) and diphenhydramine (n = 12). When specified, dosages, route(s) of administration, toxicity symptoms (including both physical and psychiatric ones), and outcomes were here reported.Conclusion: Results from the systematic review showed that the OTC misusing issues are both widespread worldwide and popular; vulnerable categories include adolescents and young adults, although real prevalence figures remain unknown, due to a lack of appropriate monitoring systems. Considering the potential, and at times serious, adverse effects associated with OTC misusing issues, healthcare professionals should be vigilant, and ad hoc preventative actions should be designed and implemented.

Misuse of Over the Counter and Prescription Only Medication by Adults Accessing Specialist Treatment Services in the UK: A Narrative Synthesis

“…Adverse consequences, such as the impact on physical and mental health has been found by others. 15 , 17 , 18…”

“…13 , 14 Other adverse consequences can include negative effects upon physical and mental health, such as potentially fatal cardiac arrhythmias. 15 - 17 Additionally, the socio-economic impact of misuse must not be underestimated and the person may be at increased risk of harm from themselves or to others. 18…”

A Focus on Abuse/Misuse and Withdrawal Issues with Selective Serotonin Reuptake Inhibitors (SSRIs): Analysis of Both the European EMA and the US FAERS Pharmacovigilance Databases

“…Antihistamines, often considered for the treatment/management of sleeping disorders [ 49 ], were frequently reported in AD ADRs. However, reports of these molecules’ abuse and diversion, either on their own or in association with ADs/other drugs, have been made available [ 15 , 17 , 50 , 51 ]. In both the EV and the FAERS datasets, antihistamines were found to be most typically associated with citalopram and fluoxetine, possibly because these molecules possess only limited sedating properties with respect to remaining SSRIs [ 52 ].…”

Safety of fexofenadine and other second-generation oral antihistamines before and after the removal of the prescription requirement in Italy and other European countries: A real-world evidence study and systematic review

“…The prescription requirement for oral antihistamine medications is strictly related to safety concerns, inappropriate use or the potential for abuse, as was observed with first-generation antihistamines. 9 For example, common side effects of these medications include sedation, decreased cognitive function, poor sleep quality, dry mouth, dizziness and orthostatic hypotension. 10 , 11 Furthermore, recreational misuse of diphenhydramine has been reported in several studies, and intoxication is associated with psychotic symptoms, disorientation and restlessness.…”