Medication-Induced Movement Disorders: A Review
Introduction
The use of medications to treat a variety of medical conditions can result in the development of movement disorders. These disorders, known as medication-induced movement disorders (MIMDs), can be caused by a variety of medications, including those used to treat psychiatric, neurologic, and cardiovascular conditions. This review seeks to discuss the prevalence, etiology, diagnosis, and management of MIMDs.
Prevalence
The exact prevalence of MIMDs is difficult to determine due to the wide range of medications that can cause the disorder. However, a recent systematic review of the literature found that MIMDs occur in 1.4-10.4% of patients taking drugs for psychiatric, neurologic, and cardiovascular conditions (Kapoor et al., 2019).
Etiology
MIMDs are typically caused by medications that affect the central nervous system, such as antidepressants, antipsychotics, sedatives, anti-epileptics, and cardiovascular agents (Kapoor et al., 2019). These medications can cause a variety of motor disturbances, including tremor, dystonia, akathisia, chorea, parkinsonism, and tardive dyskinesia.
Diagnosis
The diagnosis of MIMDs is based upon the patient’s history of drug use, physical examination, and laboratory tests. The patient’s history should include a detailed evaluation of the drugs they are taking and any recent changes in medication. The physical examination should focus on assessing motor disturbances, including tremor, extrapyramidal symptoms, and abnormal posturing. Laboratory tests may include electroencephalography (EEG), magnetic resonance imaging (MRI), and blood tests to evaluate for metabolic disturbances.
Management
The management of MIMDs depends on the type of disorder present and the underlying cause. For mild cases, discontinuing the offending medication and switching to a different medication is usually sufficient. In more severe cases, however, additional treatments may be required. These may include physical therapy, botulinum toxin injections, and medications such as anticholinergics and dopamine agonists.
Conclusion
MIMDs are a common adverse effect of medications used to treat a variety of medical conditions. The prevalence, etiology, diagnosis, and management of MIMDs have been discussed in this review. Further research is needed to identify effective strategies to prevent and treat MIMDs.
References
Kapoor, N., Monaghan, D.M., Davis, M., & Bhattacharjee, A. (2019). Prevalence, etiology, diagnosis, and management of medication-induced movement disorders: A systematic review. Movement Disorders Clinical Practice, 6(3), 433-443. doi:10.1002/mdc3.12669