Infantile spasms (IS) are characterised by neurodevelopmental regression, a unique type of seizures and a hypsarrhythmic EEG pattern. Studies recommend the medical treatment of IS as a positive short-term outcome with respect to the spasms and in the resolution of the hypsarrhythmia. However, the data are insufficient to recommend medical treatment with respect to improving the long-term outcome. The adrenocorticotropic hormone and prednisolone are recommended for treatment of IS, although side effects are common. Vigabatrin is also recommended; IS caused by tuberous sclerosis seems to respond especially well.