[Systemic adverse effects of topical ocular instillation of atropine in two children]

A medication-related cause must be sought when unusual symptoms occur. Topical treatments, including eye drops, whose side effects are more common in exposed children, need to be verified. We report here the cases of two children who developed systemic symptoms after the administration of atropine-based mydriatic eye drops. A 6-month-old boy was admitted to the emergency department with acute urine retention lasting 36h. Investigations identified only eye drop treatment 3h before the onset of symptoms, with 2 drops of homatropine 1 %, as a cause. No other urinary retention was observed during the 1-year follow-up. A 2-year-old boy was admitted to the emergency department for drowsiness, thirst, and dry mouth 30min after the administration of three eye drops of atropine 1 % instead of atropine 0.3 % (error made by the pharmacy). Symptoms disappeared after 6h. Both observations highlight the possible side effects related to mydriatic eye drops. Indeed, because of small penetration of such medications in the eye, a high concentration of the active part of the medication is contained in each drop. In young children, at least 20 to 40 % of the volume of a drop drains into the nasolacrimal duct and thereby into the systemic circulation, without passage through the liver. A close national pharmacologic vigilance follow-up has been set up for atropine-based mydriatic eye drops in young children, who are the most exposed to systemic and potentially severe complications of these medications. We emphasize the appropriate procedure for the use of eye drops in young children to limit systemic passage, with only a 0.3 % maximum atropine concentration in infants, compression of the internal angle of the eye for at least 1min, and at least a 15-mins interval between two eye drop administrations.