Ophthalmic Atropine: A Typical Anticholinergic Toxidrome From an Atypical Old Culprit

Included on the World Health Organization Model Lists of Essential Medicines, atropine remains a cornerstone medication that is used for a myriad of clinical indications. Systemically, atropine carries indications for the treatment of asymptomatic and symptomatic bradycardia, reduction of salivation and bronchial secretions prior to surgery, and as an antidote for a variety of poisoning agents (i.e., carbamate or organophosphate insecticides, nerve agents, muscarine-containing mushrooms). Topically, atropine is administered via the ophthalmic route for the treatment of cycloplegia, mydriasis, and amblyopia or may be administered sublingually to treat chronic sialorrhea. As an anticholinergic, supratherapeutic concentrations of atropine result in a toxidrome typical of other anticholinergic medication overdoses. However, it is easy to overlook atropine as the causative agent when being administered topically, potentially resulting in an unnecessarily extensive and complicated workup. This case report describes the systemic absorption of atropine administered through the ophthalmic route at normal doses, resulting in stroke-like symptoms in an adolescent male. Upon identifying that the patient was being treated with atropine ophthalmic drops prior to hospital arrival, a dose of intravenous physostigmine was administered, resulting in complete reversal of all toxidrome symptoms.