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The majority of MIT are posture holding or kinetic, but some medications (especially lithium, DBAs, valproic acid) can cause resting tremors. PD is a classic cause of resting tremor that typically occurs unilaterally and improves with motion but can recur as re-emergent tremor when a sustained posture is maintained. Resting tremor typically worsens with distraction and goes away during sleep. Physiological tremor is an action tremor that is mediated by both central and peripheral mechanisms.17,18 It consists of low-amplitude, high-frequency (8–12 Hz) oscillations depending on the stiffness, mass, and other properties of the tremoring body part. EPT can be very similar in appearance and characteristics to ET when EPT becomes clinically symptomatic. Drug-induced tremors typically are symmetric or equal on both sides of the body.
Drug-Induced Abnormal Involuntary Movements: Prevalence and Treatment
Ms A, a 23-year-old woman, was brought to the emergency department (ED) by police because of increasingly disruptive behaviors in her apartment building over the past week. She described hearing neighbors accuse her of poisoning their pets; moreover, she believed that they were “bugging” her apartment and watching her through her TV. Her medical history was notable for having systemic lupus erythematosus and chronic kidney disease. Although she had an episode of depression during college, she had not received psychiatric treatment for the past 2 years. The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions.
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Evolution of Treatment Modalities for PTSD
Another important part of the history is the family history of inherited and genetic disorders (like Huntington’s disease and Wilson’s disease) that affect the basal ganglia and typically present with abnormal movements (including chorea, athetosis, and dystonia). Similarly, a substance use history that includes prior manifestations of intoxication or withdrawal should be obtained. Both therapeutic and illicit drugs can cause neurological adverse effects, including movement disorders. The most common causes of drug-induced movement disorders are dopamine receptor blocking drugs, including antipsychotics and antiemetics (Table 1).
There is rigidity in neuroleptic malignant syndrome whereas myoclonus, hyperreflexia with clonus, and mydriasis are more common in serotonin syndrome. Early recognition of a drug-induced movement disorder is essential to allow for prompt intervention. This includes stopping the offending drug, supportive care, and sometimes other pharmacological treatment. A number of medications can cause parkinsonism because they block the dopamine receptor and thereby mimic the symptoms of PD that are caused by loss of dopamine neurons in the brain. Reviewing a patient’s medications is therefore a critical step for a neurologist when seeing someone with parkinsonism. Anti-psychotics and anti-nausea treatments make up the bulk of the problematic medications, although there are other medications that can also cause parkinsonism.
- Additionally, there is a poor response to typical antiparkinsonian drugs, including levodopa, dopamine agonists and anticholinergic drugs.
- Often, the tremors occur when a person dependent on alcohol stops taking alcohol.
- Alcohol abuse may also cause bilateral flapping tremors, characterized by arrhythmic interruptions of sustained voluntary muscle contraction.
- If the drug is continued, drugs typically used for essential tremor (for example, propranolol) can occasionally be beneficial.
- Resuming the offending drug or changing to an atypical antipsychotic is sometimes required.16 In patients with a chronic psychotic disorder clozapine is preferred.
- Resting tremor (as typically occurs in DIP or PD) is commonly 4–6 Hz in frequency and occurs when the affected body part is fully supported without ongoing voluntary muscle contraction.
Muscular Dystrophy: Options for Complication Management
Methylenedioxymethamphetamine (MDMA), better known as ecstasy, is also known to cause movement disorders in addicts. Finally, it will be important to further define the most vital anatomical structures for the generation of tremor in the CNS and further understand the physiology of these interconnected players. It will also be important to develop further knowledge of neurotransmitters and their receptors that may influence tremor or actually suppress it. Hopefully this further knowledge will lead to better therapeutics for pathological tremors and allow us to develop less tremorogenic drugs. Stop the offending drug, and give an drug induced tremors intravenous or intramuscular anticholinergic drug (such as benzatropine or trihexyphenidyl (benzhexol) hydrochloride). As the injectable drug has a short half-life it is followed by a short course of oral anticholinergic drugs.4,5,7 Benzodiazepines have also been used.
Table 1 – Drug-induced movements disorders
Tremors or Drug-Induced Movement Disorders (DIMD) may harm your quality of life and general well-being. You may find it challenging to perform easy tasks, which may, in turn, affect your social functioning and interpersonal communication. You may also lose your independence as you’d need help performing easy tasks. Tremors may also result in other symptoms like depression and anxiety, which may have severe consequences. Alcohol tremors primarily affect the hands, but they affect the legs and arms in some circumstances. The tremors manifest approximately 8 hours after you stop drinking and peak about 30 hours after your last drink.
Synopsis of Chemical and Drug-related Agents That Cause Movement Disorders
- In rare instances where clinically appropriate, deep brain stimulation surgery may be necessary to ameliorate the tremor.
- In extreme cases, it may also induce intracranial hemorrhages, comas, or seizures.
- Another important aspect of the history is a review of the neurologic and neurodevelopmental history.
- You may also lose your independence as you’d need help performing easy tasks.
- The most commonly implicated drugs include antipsychotics, antiemetics (metoclopramide and prochlorperazine) and some calcium channel antagonists with dopamine receptor blocking properties (cinnarizine and flunarizine).
- The speed of the tremor can be an important way to determine its cause.
- Drug-induced parkinsonism is a movement disorder that is caused by taking medication that interferes with dopamine transmission in the brain.
APDA has created a list of Medications to be Avoided or Used With Caution in Parkinson’s Disease. It is important to note that there are anti-psychotics and anti-nausea medications which do not cause parkinsonism and can be used safely by people with PD. We performed a PubMed literature search for published articles dealing with MIT and attempted to identify articles that especially dealt with the medication’s mechanism of inducing tremor. Contact your provider if you are taking a medicine and a tremor develops that interferes with your activity or is accompanied by other symptoms. Your health care provider can make the diagnosis by performing a physical exam and asking about your medical and personal history. We have both inpatient and outpatient treatment programs, so you are free to select a program that suits you best.
Obtaining a complete psychiatric history from someone who has developed abnormal muscle movements is crucial to refining the differential diagnosis and mapping out a treatment plan. Details of the location and nature of the abnormal movements, their onset and progression, and their aggravating and relieving factors are essential. Another important aspect of the history is a review of the neurologic and neurodevelopmental history. A history of a seizure disorder might provide insight into the causes of stereotypic movements. A history of a recent stroke might contribute to athetosis, while a traumatic brain injury or Parkinson’s disease (PD) can cause akathisia or tremors. Similarly, patients with autism spectrum disorder often have stereotypic movements, while motor tics are often comorbid with attention-deficit/hyperactivity disorder (ADHD), Tourette syndrome, or obsessive-compulsive disorder (OCD).
Symptoms
Other drugs can cause tremor, presumably by blockade of dopamine receptors in the basal ganglia (dopamine-blocking agents), by secondary effects such as causing hyperthyroidism (amiodarone), or by other mechanisms. We will attempt to discuss what is known and unknown about the pathophysiology of the most common MITs. No good evidence exists regarding the management of tardive drug-induced movement disorders.15 Treatment usually consists of withdrawing the offending drug, and a trial of a combination of drugs. Resuming the offending drug or changing to an atypical antipsychotic is sometimes required.16 In patients with a chronic psychotic disorder clozapine is preferred. Most recently, vesicular monoamine transporter 2 inhibitors deutetrabenazine and valbenazine have been proposed as treatment options.17,18 Other oral drugs have been tried, including tetrabenazine, amantadine and propranolol. Akathisia is a common, but often under-recognised, drug-induced movement disorder that can occur as an acute, subacute or tardive reaction.
However, symptomatic treatments are indicated to reduce motoric and psychological symptoms that impair social function and worsen quality of life. Recommended treatments for each type of AIM are summarized in Table 21,20–30 and described below. Some of these treatments are within the scope of practice of primary care physicians; others will require referral to specialists. Postural tremors occur for example, when the arms are extended, such as when holding a tray. Action tremors occur for example, when the arm is moving toward the mouth to eat. The mainstay of treatment includes resuming anti-parkinsonian drugs, usually via nasogastric tube because of the dysphagia resulting from severe parkinsonism.
