Drops of madness? Recreational misuse of tropicamide collyrium; early warning alerts from Russia and Italy

Background: Tropicamide is an antimuscarinic drug usually prescribed as an ophthalmic solution to induce short-term mydriasis and cycloplegia. Over the last 2 years, tropicamide has been reported in both Russia and Italy to be self-administered intravenously (IV) for recreational purposes. Methods: The literature on tropicamide was searched in PsycInfo and Pubmed databases. Considering the absence of peer-reviewed data, results were integrated with a multilingual qualitative assessment of a range of Web sites, drug fora and other online resources (i.e., e-newsgroups, chat rooms, mailing lists, e-newsletters and bulletin boards): between January 2012 and January 2013, exploratory qualitative searches of more than 100 Web sites have been carried out in English and Italian using generic and specific keywords such as "legal highs," "research chemicals," "online pharmacy," "tropicamide," "mydriacil," "tropicacyl," "visumidriatic," "online pharmacies" and "tropicamide recreational abuse" in the Google search engine. Results: Misuse of tropicamide typically occurs through IV injection; its effects last from 30 min to 6 h, and it is often taken in combination with other psychoactive compounds, most typically alcohol, marijuana and opiates. Medical effects of tropicamide misuse include slurred speech, persistent mydriasis, unconsciousness/unresponsiveness, hallucinations, kidney pain, dysphoria, "open eye dreams," hyperthermia, tremors, suicidal feelings, convulsions, psychomotor agitation, tachycardia and headache. Discussion/conclusions: More large-scale studies need to be carried out to confirm and better describe the extent of tropicamide misuse in the European Union and elsewhere. Health and other professionals should be rapidly informed about this new and alerting trend of misuse.