“Isoflurane Narcotherapy” in Depression: Methodological Issues

Preliminary observations of our study on the therapeutic effects of deep anesthesia with insoflurane in psychiatric patients have been reported elsewhere1. After awakening from the first anesthesia, antidepressant effects were observed in 9 of the 11 patients, who had been classified as depressives (by Research Diagnostic Criteria, RDC) refractory to conventional antidepressant drug therapy. The therapeutic effect diminished gradually over several days unless another session of “isoflurane narcotherapy” (ISONAR) was given. That study was uncontrolled; currently, a double-blind controlled study comparing the efficacy of electroconvulsive treatment (ECT) with ISONAR is in preparation. A synopsis of methodological and theoretical considerations is presented here as a consequence of many observations and discussions in this explorative state of affairs. If a potentially new mode of treatment such as ISONAR is to be given an optimal chance for proof of efficacy, it is important that the appropriate clinical indication and administration procedure be established (the two most important factors in pharmacological therapy).