Pancytopenia From "Mesantoin"

Mesantoin (3-methyl-5,5-phenylethyl hydantoin) is one of the newer anticonvulsant drugs and is chemically and pharmacologically related to dilantin (diphenylhydantoin sodium). Kozol 1 and Loscalzo 2 reported that this drug is effective the control of grand mal seizures and may be useful patients who are refractory or intolerant to dilantin. They noted no serious toxicities, although in about 40 per cent of the cases the lymphocytes were moderately increased at the expense of the neutrophiles. 2 Cutaneous eruptions have occurred 4.5 to 14 per cent of the cases, 3 and Ruskin 4 recently reported a fatal case of dermatitis bullosa medicamentosa due to mesantoin. A search of the literature reveals only mention of 1 case of serious blood dyscrasia ascribed to mesantoin alone. 5 On review of the case of fatal aplastic anemia following the use of tridione (trimethadione) reported by Harrison and his co-workers; 6 it is