Introduction: We report two cases of acute confusional syndrome (ACS) after instillation cyclopentolate eye drops in usual doses during the regular ophthalmic checkups.

Patients: Case 1: a seven year's child who commenced to present malar erythema a half an hour later and after instilling cyclopentatolate; 2 hours later, the child presented an acute confusional state; after testing with complementary test was concluded that the cause was the cyclopentolate and the patient was under observation. Case 2: a seven year's child who was admitted to the emergency service affected by neurological symptons after the instillation of the cyclopentalote eye drops 8 hours before; no additional tests were taken and the patient was under observation until the home discharge.

Conclusions: The use of this drug in regular doses can produce ACS in some children. It is only required observation if the clinical use is not excessive. Can be administered physostigmine.

A case is reported of an acute confusional state due to the use of cycloplegic eye drops in a previously healthy 6-year-old girl: Nervousness, hallucinations and unintelligible language. This adverse reaction was temporary and without after effects. We think that this case is of interest because parasympatholytic agents of topic ocular use can produce systemic side effects. The public health and health care personnel should be aware of this and parents should be warned about this possibility.