Haematological adverse effects associated with olanzapine in adolescents with anorexia nervosa: Three case reports

Objectives

To describe haematological adverse effects in adolescents with anorexia nervosa who are taking olanzapine.

Methods

Case series report.

Case report

The reported cases (two female patients and one male) were found to have blood test abnormalities after starting olanzapine and to rapidly recover their platelet and neutrophil values after the drug was discontinued. Low haemoglobin values persisted longer than observed in other series. These abnormalities became more noticeable when the dose of olanzapine was increased to 5 mg/day (initial dose 2.5 mg/day). It should be noted that two of the patients already had values indicative of mild neutropenia before they started the antipsychotic drug, and that these worsened as they continued taking the drug. In one of the patients there was only a decrease in neutrophil values, as well as mild anaemia.

Conclusions

This first case series of haematological abnormalities in adolescents with anorexia nervosa who are taking olanzapine found values corresponding to pancytopenia in two of the three cases reported. It would be worthwhile to consider heightening haematological surveillance in this population when starting treatment with olanzapine and rethinking our knowledge regarding the frequency of these side effects.