Lithium-Induced Movement Disorders

Monitoring and Diagnosis

Regular serum lithium monitoring is essential, especially during acute treatment phases, with measurements twice per week until stabilized, as emphasized by the FDA label, which highlights that lithium toxicity occurs at doses close to therapeutic concentrations, making vigilant monitoring crucial 1, 2
The American Academy of Pediatrics recommends that drug-induced Parkinsonism from lithium manifests with motor symptoms of tremor, rigidity, postural instability, and bradykinesia 3
Dopaminergic imaging, such as DaTscan SPECT imaging, can clarify the diagnosis by differentiating drug-induced parkinsonism from neurodegenerative Parkinson's disease, and is recommended by the Genetics in Medicine society 4, 5

Obtain serum lithium level immediately to rule out toxicity, and evaluate hydration status and check for precipitating factors, including dehydration, medication interactions, or renal impairment, as recommended by the Praxis Medical Insights society 2, 7
The Journal of the American Academy of Child and Adolescent Psychiatry recommends that antipsychotic medications can also induce Parkinsonism, which may complicate the clinical picture if patients are on multiple psychotropic agents 3, 6
Reducing the daily lithium dosage typically improves motor symptoms, and drug-induced Parkinsonism may be treated by adding an anticholinergic agent, adding a dopaminergic agonist, or decreasing the antipsychotic dosage, as suggested by the Pediatrics society 3

Avoid concomitant NSAIDs which can increase lithium levels and precipitate toxicity, as warned by the Praxis Medical Insights society 2
Temporarily suspend lithium during intercurrent illness, IV radiocontrast administration, bowel preparation, or prior to major surgery, as recommended by the Praxis Medical Insights society 2, 7