The comparative efficacy and safety of ACTH (110 IU/m2 once daily for 15 days) and vigabatrin (100-150 mg/kg/daily in bid doses) was evaluated by a retrospective analysis of medical records of 42 infants (21 in each group) with infantile spasms and hypsarrhythmia treated at the Universite de Montreal, Hopital Sainte-Justine, Montreal, Canada. Seizure response was similar in the ACTH and vigabatrin-treated infants at 12 month follow-up (61% vs 71% benefited, respectively), but vigabatrin was better tolerated than ACTH. Side effects of ACTH in 5 patients included hypertension and Cushing’s syndrome, requiring discontinuation of therapy in 3; hypotonia and sleep disturbance in 3 vigabatrin-treated patients were transient and did not require drug withdrawal. No cases of visual field restriction were encountered. Vigabatrin was recommended as the first-line treatment for infantile spasms. 
COMMENT. Vigabatrin and ACTH appear to show equal effectiveness in the treatment of infantile spasms, but the plethora of reports of vigabatrin-induced visual field defects in adults are a concern. The majority of the cases cited are in adults, but asymptomatic visual field constriction also occurs in children. Two affected children, ages 10 and 15, treated with vigabatrin in doses ranging from 1000 to 3500 mg/kg, are reported from the Children’s Hospital, University Hospital of Kuopio, Finland. 
At least with long-term therapy, vigabatrin should be used with caution in infants, until more is known about the risk factors involved.