The boy (case 1) at the age of 12 weeks started having attacks and jercked after the first injection of triple vaccine (diphtheria, retanus and whole cell pertussis) The electro-encephalogram (EEG) confirmed the typical features of hypsarrhythmia. Intramuscular ACTH was commenced for 2 weeks. No problem was reported until the age of 9 years when he started having attacks of jercking. He was treated with sodium valproate. The boy of the second case was a first cousin of case 1. At the age of 11 years the boy had momentary black outs. The EEG showed findings of idiopathic epilepsy. Treatment with sodium valproate was commenced. The children of both cases belong to a family in which there is a trendency to seizures. It seems unlikely the triple vaccine produced the infantile spasms in case 1.