RESUMO
Methylphenidate- and amphetamine-based psychostimulants are the most common medications used to treat the symptoms of attention-deficit/hyperactivity disorder in children. Ocular side effects including dry eyes, mydriasis, accommodation disturbance, and blurry vision are listed in the product monograph but interestingly, are rarely reported in the paediatric literature. Our patient, a 9-year-old boy, presented a significant decrease in visual acuity secondary to accommodation disorder after being treated with methylphenidate hydrochloride controlled release (Biphentin) and lisdexamfetamine (Vyvanse). The unusual acute adverse effect, altered accommodation leading to a decline in visual acuity, emphasizes the importance of considering any change in vision following the introduction of psychostimulant medication as a potential adverse effect. This case highlights the importance of pharmacovigilance especially in paediatrics where data are lacking.