Quetiapine-Associated Hypothyroidism in Young Female Patients: A Report of Three Cases

Quetiapine is an atypical antipsychotic indicated for schizophrenia and bipolar disorder. In some rare cases quetiapine may induce a dose-related decrease in thyroxine levels. We present 3 cases of young female patients with various psychiatric diagnoses who presented with quetiapine-associated hypothyroidism, 2 of them with an increase in TSH. The time of recovery varied. Shorter times may be associated with discontinuation of quetiapine rather than with thyroxine substitution while continuing with quetiapine. Monitoring of thyroid function at least in quetiapine-treated patients with a history of or susceptibility to thyroid disease is recommended. If used concomitantly with other thyreostatics, such as lithium, this may also be warranted for young patients and those with high quetiapine doses. Further studies on the relevance of patients’ age and sex and on the reversibility of quetiapine-induced hypothyroidsim are needed.