DOUBLE-BLIND COMPARISON OF THE SIDE-EFFECT PROFILES OF DAILY VERSUS ALTERNATE-DAY DOSING SCHEDULES IN LITHIUM MAINTENANCE TREATMENT OF MANIC-DEPRESSIVE DISORDER

The side-effect profiles of daily vs. alternate-day lithium carbonate dosing schedule were compared in a double-blind study of 50 manic-depr essive patients. Following a 3-month period on daily lithium maintenan ce treatment the patients were randomly allocated to daily or alternat e-day lithium dosing aiming at maintaining the same 12-h serum concent ration as prior to allocation (median 0.7 mmol/l). The daily and alter nate-day median lithium doses were 700 mg and 1200 mg, respectively, T here was no significant correlation between changes in the side-effect scores on the UKU side-effect rating scale and lithium dosing schedul e (ordinal logistic regression), although analysis revealed a trend in favour of alternate-day dosing with respect to polyuria/polydipsia an d diarrhoea (loose stool). The study thus lends no support to the hypo thesis that lithium-related side-effects can be diminished by extendin g the interval between lithium doses from 1 to 2 days.