Cyclopentolate is a frequently used topical mydriatic and cycloplegic drug for clinical diagnosis and preoperative evaluation. Cyclopentolate has rare systemic side effects as well as dose-dependent ocular effects. A six-year-old boy was admitted to the Ophthalmology Outpatient Clinic because of strabismus, and a total of 24 drops (3 drops for per eye for 4 times) cyclopentolate were instilled. Six or seven minutes after the last dose a gait ataxia was observed. The patient was admitted to the Emergency Department with the findings of gait ataxia, incoherent speech, smacking of the lips and continuous laughing. His blood pressure and pulse were normal. The pupils were maximally dilated and not reactive to light. His neurologic examination revealed no other pathologic findings. Laugh attacks and incoherent speech recovered in 40 minutes. Smacking of the lips, gait ataxia and dizziness lasted for five hours. There were no systemic or neurologic physical findings except for pupillary dilatation. He was discharged after 12 hours of clinical follow-up without any sequelae. Ophthalmologists should be aware of these infrequent systemic adverse effects of cyclopentolate and should warn the patients about possibility of these effects.

Keywords: siklopentolat, zehirlenme, deliryum, cyclopentolate, poisoning, delirium