Olanzapine-induced restless leg syndrome (Willis–Ekbom disease): A case report

Restless leg syndrome, also known as Willis–Ekbom disease, is a neurological sensorimotor disorder accompanied by an irresistible urge to move the legs with a fluctuating course of symptoms. It is a common disorder affecting all ages, with existing comorbidities and positive family history being associated with increased prevalence. Herein, we present a case of a 51-year-old female diagnosed with the bipolar affective disorder who developed restless leg syndrome following the use of olanzapine. Olanzapine is a second-generation antipsychotic which can cause restless leg syndrome due to its anti-dopaminergic action on the nervous system, particularly the spinal cord. Existing literature on olanzapine-induced restless leg syndrome has suggested managing this disorder by reducing the dose or replacing olanzapine with other drugs such as clonazepam, quetiapine, and aripiprazole. In our case, olanzapine was not replaced with other medications as the patient showed a significant improvement in bipolar affective disorder symptoms using olanzapine. Instead, clonazepam was added to the treatment regimen which was scheduled to be taken before olanzapine.