• affective disorder;
  • folate;
  • lithium

Serum and red cell folate concentrations were estimated in 68 affective disorder patients taking lithium prophylactically, 65 of whom had bipolar disorder. The number of hospital admissions, the frequency of use of additional mood altering treatments and the Affective Morbidity Index were calculated for the 2 years of the study. Contrary to other findings, there were no differences between the folate concentrations for different severities of affective morbidity. These results question the rationale of prescribing folic acid preparations for lithium-treated bipolar disorder patients, but the authors indicate that folate concentrations may be low in lithium-treated unipolar depressives.