The effect of enalapril on serum lithium levels in healthy men.

Abstract

Although no statistically significant differences between mean serum lithium level during treatment either with lithium alone or with lithium/enalapril were found, it is possible that the low dose of enalapril and low serum lithium levels employed for subject safety may have resulted in a type II statistical error. If enalapril doses or initial serum lithium levels were similar to those described in case reports, a significant difference in mean serum lithium levels may have been observed. While a predictable interaction between lithium and enalapril probably does not occur in all patients, factors such as enalapril dose, serum lithium level before addition of enalapril, or the presence of heart disease may make such an interaction more likely. At the levels of lithium and enalapril used in this study, elevated serum lithium concentration does not appear to be a universal event, but physicians must exercise appropriate caution.