Medication-induced Movement Disorders

Nearly all, if not all, medications have side effects. More powerful medications are likely to have more powerful side effects. It is not surprising, then, that medications powerful enough to reverse the symptoms of psychoses like mania, depression, or schizophrenia can produce powerful side effects, some of which are undesirable. One name for these powerful anti-psychotic medications is "neuroleptics." The most visible of the side effects are movement disorders; that too is natural, considering that the nervous system controls our movements, and the medications that help with mental disorders must do so by affecting the nervous system, especially the brain. Some anti-psychotics oppose the action of dopamine, a chemical that transmits impulses from one nerve cell to another in the brain. This decreases the transmission of impulses and often calms the patient. Other drugs increase the transmission of impulses (used for depressed patients) by increasing the concentration of other neurotransmitters. These may make the patient more activated and motivated. Anti-psychotics are sometimes prescribed for their temporary calming effects on manic patients, but then lithium or, more likely, a valproic acid-based medication is prescribed for long-term management. 

One factor that increases the side effects of neuroleptics is that there is a "blood-brain barrier" that makes it difficult for drugs to get from the blood into the brain. Thus large doses may be necessary in order to get an effective amount into the brain; meanwhile, other organs are getting a higher concentration of the drug. If they are sensitive to its action, side effects occur. Recent research indicates that lower doses than are usually prescribed are just as effective for some disorders as the higher doses. That is important because lower doses cost less and produce fewer or less severe side effects. 

The following are the movement-related side effects that may be produced by neuroleptics, sometimes while taking them, and sometimes when reducing or stopping their use. If you or a loved one is experiencing these symptoms, contact your prescribing physician immediately.  There are alternative medications that can be prescribed and sometimes an additional medication to control the movement disorders. 

Neuroleptic-Induced Parkinsonism: This disorder gets its name from its resemblance to Parkinson's disease; the symptoms may include tremor, rigidity, or inability to move. 

Neuroleptic Malignant Syndrome (NMS): This very serious syndrome can involve very severe muscular rigidity, inability to eat, confusion or coma, unstable blood pressure, and other physical symptoms. This is truly a case in which the cure (brought about by taking neuroleptics) may be worse than the disease (even if the disease is schizophrenia). The symptoms may disappear within a week or so after the patient stops taking neuroleptics; it may be helpful to give the patient drugs that increase the action of dopamine (which was decreased by the anti-psychotic medication). Patients must be hospitalized and closely monitored. You can click here for more information on NMS.

Neuroleptic-Induced Dystonia: The dystonia (muscle spasms) is visible in the form of abnormal posturing (twisting) of the head, neck, or trunk that may appear soon after neuroleptics are started or the dosage is increased. 

Neuroleptic-Induced Acute Akathisia: Irresistible restless and repetitive movements may appear; the person is unable to hold still, and this, too, may happen soon after neuroleptic medication is started or the dose is increased. 

Neuroleptic-Induced Tardive Dyskinesia (TD) TD is the best-known and most common of the side effects of neuroleptics. It is a tic-like disorder, involving various motions in the face and mouth area or extremities. Chewing motions and protrusion of the tongue are frequent and unsettling symptoms that may occur when medication is stopped after a period of usage, or even with continuing usage; TD frequently attends medication periods of 2 years, or less in older patients. The movements may appear grotesque; they sometimes remit, but often persist until the patient is put back on medication or, if already on an anti-psychotic, until the dose is increased. This presents a Catch-22 situation for patients, who may have to choose among schizophrenia, TD, and getting on a spiral staircase of increasing anti-psychotic medication. 

Medication-Induced Postural Tremor: This less serious disorder is a fine tremor that occurs when an individual on neuroleptics tries to maintain a particular posture. 

Medication-Induced Movement Disorder Not Otherwise Specified: This is a category for all other medication-induces movement disorders, particularly for any movement disorder that is not caused by a neuroleptic medication. 

Other Medication-Induced Disorder.