A Year's Experience of Insulin Therapy in Schizophrenia

WHAT is known as the insulin shock therapy of schizophrenia, introduced by M. Sakel in 1933 at the Potzl Clinic, Vienna, has been in use at Moorcroft House, Hillingdon, since January 1, 1937. This communication summarizes the experiences of 1937, 24 cases being completed during the period. The technique of the authors has been described in an article contributed to the Lancet (1937), which does not require any essential modification. Throughout 1937 we have begun treatment at the hour of 7 a.m., and the total hypoglycaemic period has seldom been allowed to exceed five hours. In exceptional cases in which coma has arrived very late we have extended the period up to six hours. This means that interruption usually occurs at the latest at 12 noon, a time {convenient for hospital administration, as it allows patients to be bathed and dressed and ready for lunch at the usual hour of 1 p.m. From experience we believe it to be wise to drop the term " shock ", because we feel that in some quarters there is a tendency to magnify the dangers of insulin therapy. Muller (1937) in a series of 495 cases treated in Swiss hospitals, gives the mortality rate as 0.5%, and it is probable that with improvement and standardization in technique this mortality rate may be still further reduced. With proper supervision and immediate access to the appliances necessary to deal with emergencies, very few are really alarming. We return later to this question, but would add here that it is easy to become lulled into a sense of security by the regular passage of days or weeks of treatment without incident. Emergencies come with dramatic suddenness, and fatalities would be certain were there anv relaxation in vigilance or lack of essential appliances. The brand of insulin has been varied. For the first six months we used a brandI of pure crystalline insulin, changing at the end of this period to a gland extract. There has been no urticaria in the whole of our series, and no differences were observed in the effects of the two preparations. Dosage. Even after a year it is not easy to give any precise information about the average dosage of insulin required to produce hypoglycaemic coma. We aim at -producing coma in the third hour of hypoglycaemia. Coma has been produced bv 15 units, while another case required over 400 units. This wide variability in sensitivity to insulin is very striking, and dosage cannot be forecast with any accuracy. Insulin tolerance appears to vary in the same patient during the course of treatment, some patients developing an increased resistance, others an increased sensitivity. In the great majority of our cases, dosage has been decreased after the initial coma dose has been reached. For example, if the initial coma dose is found to be 100 units. that dose may be reduced to 90, 80, or even 70, units later in the treatment, to produce satisfactory coma. We agree with Muller (1937) that this variability in sensitivity bears no relation to mental improvement or the reverse. Effect of dosage on blood-sugar. Blood-sugar estimations that have been made show a fairly constant series of changes. Within an hour of the injection the bloodsugar falls to 30 mgm. per 100 c.c. , or even less. It remains at about that level during the whole of the hypoglycwmic period. Half an hour after interruption, when