Drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is the most common drug-induced movement disorder and is most commonly associated with antipsychotic drugs, monoamine reuptake inhibitors, and calcium channel blockers. DIP manifests as a typical movement disorder, which makes it practically indistinguishable from idiopathic Parkinson's disease (PD) and requires differential diagnosis. DIP symptoms develop fairly quickly (hours to weeks) after the antipsychotic is started or after the dose is increased. Therefore, DIP is predominantly a clinical diagnosis that must be kept in mind when a patient develops typical symptoms during treatment onset or increasing the dose of drugs that most often lead to such an adverse reaction (ADR). DIP evaluation includes using the Naranjo algorithm, which helps assess a causal relationship between drug intake and the development of parkinsonism symptoms. The primary DIP treatment is the reduction of the dose of the inducer drug, or its cancellation, or replacement with another drug. In patients with schizophrenia and antipsychotic-induced DIP, dose reduction, replacement with another medication, or prescription of a drug with anticholinergic activity may be possible. The awareness of the doctor and the patient about the possibility of developing this ADR is crucial in the prevention of DIP. Therefore, choosing a drug with the lowest risk of developing DIP is necessary for pharmacotherapy.