A 4.5 year old boy with cerebral palsy presented with seizures associated with facial flushing and tachycardia following the instillation of 1% cyclopentolate, a commonly used mydriatic in paediatric practice. He had no prior history of convulsions. This case demonstrates the uncommon, though serious, atropine-like side effect of cyclopentolate eyedrops (Cyclogyl, Alcon) in usual dosage in a brain damaged child without an epileptic focus.