Original ArticlesThe Effect of Repeated Bilateral Electroconvulsive Therapy on Seizure ThresholdScott, Allan I. F. M.D., M.Phil., M.R.C.Psych; Boddy, Harold M.B.Ch.B Author Information Andrew Duncan Clinic, Royal Edinburgh Hospital, Edinburgh, Scotland, United Kingdom Received March 9, 1999; accepted June 9, 1999. Address correspondence and reprint requests to Dr. A. I. F. Scott, Andrew Duncan Clinic, Royal Edinburgh Hospital, Edinburgh EH10 5HF, Scotland, U.K. The Journal of ECT: September 2000 - Volume 16 - Issue 3 - p 244-251 Buy Abstract Seizure threshold was measured by empirical titration in 28 patients referred for bilateral electroconvulsive therapy to treat depressive illness at the outset of treatment and after another six treatments. No patient was given antiepileptic drug treatment, and anesthetic technique and concomitant psychotropic drug treatment were fixed. The average (± SD) initial seizure threshold measured by set charge was 79.5 mC (± 33.4 mC), and this increased to 95.5 mC (± 37.9 mC). The average percentage increase was 22.8% (95% confidence interval, 13.7% to 31.8%). The seizure threshold measured by set charge did not change in 15 patients (54%), and there was no significant relation between change in seizure threshold and patient sex, change in seizure duration measured by cuff technique, or global clinical improvement during the course of treatment. © 2000 Lippincott Williams & Wilkins, Inc.