Are there ethnic differences in lithium pharmacokinetics and side-effects?

Possible ethnic differences in the pharmacokinetics of lithium carbonate were systematically examined in Caucasian and Afro-Caribbean volunteer subjects under standardized conditions. The two groups did not differ with regard to weight, age or renal function. Rates of absorption were similar, but there was a non-statistically significant trend towards more rapid distribution and elimination, smaller area under the serum curve and greater urinary excretion in the Caucasian group. There were no differences in side-effects. The results support the view that ethnic differences in blood levels found with other psychotropic drugs are due to altered drug metabolism and suggest that lithium pharmacokinetic data derived from Caucasian subjects can be safely extrapolated to Afro-Caribbean.