Tardive dyskinesia and dystonia are both caused by increased signaling of nerves to muscles, resulting in involuntary muscle contractions and movements. Depending on the length of time taking certain medications, these disorders can become irreversible.
This article will discuss the different symptoms, causes, and treatments for tardive dyskinesia and dystonia.
Symptoms
Tardive dyskinesia and dystonia are both movement disorders that result from increased neuromuscular signaling from the brain to different muscles of the body. While similar, tardive dyskinesia and dystonia are different conditions presenting with different symptoms.
Tardive Dyskinesia
Tardive dyskinesia is characterized by irregular, involuntary movements most commonly in areas of the face, eyes, and mouth, including the jaw, tongue, and lips. Common involuntary movements seen in patients with tardive dyskinesia include abnormal tongue movements, lip smacking or puckering, grimacing, and excessive blinking.
Symptoms may also occur in the trunk, arms, and legs. These movements can be rapid, jerky, and twitch-like, but sometimes they are slow and writhing as well.
“Tardive” means late onset, indicating that these abnormalities of movement typically arise in people who have been taking certain medications for an extended period of time. This condition may persist even after medication is discontinued.
Dystonia
Dystonia describes involuntary muscular contractions that cause sustained and repeated motions or abnormal postures. Dystonia most commonly affects the head, face, and neck, and is often painful and worsens with voluntary movement.
Unlike tardive dyskinesia, which typically takes a longer time to develop, dystonia can occur within hours or days (usually within the first five days) of initiating treatment with an antipsychotic medication or increasing medication dosage.
Causes
Tardive Dyskinesia
Tardive dyskinesia occurs as a side effect of taking certain medications, like antipsychotics to treat mental disorders and those medications in the category of dopamine receptor blockers. It may take months or years of taking these medications for symptoms of tardive dyskinesia to develop.
The antipsychotic drugs chlorpromazine, haloperidol, and perphenazine are used to treat schizophrenia and other mental disorders. They have all been significantly linked to causing symptoms of tardive dyskinesia.
Tardive dyskinesia may appear quicker in older people who have been taking antipsychotic medications for a shorter period of time. Risk factors for developing tardive dyskinesia from use of antipsychotic medications include:
Being female Being of African-American ethnicity Having a prior injury to the brain or history of dementia
Dystonia
Dystonia has a variety of different causes. Like tardive dyskinesia, dystonia can be acquired and drug induced, resulting as a side effect from taking antipsychotic medications.
Other acquired causes of dystonia include:
InfectionsTumorsExposure to toxinsBrain injuries from head trauma, brain surgery, or during development before birth
Other forms of dystonia can be inherited through different genetic mutations, and dystonia can occur idiopathically, meaning that the underlying cause is unknown.
Diagnosis
Tardive dyskinesia and dystonia are typically diagnosed by a neurologist based on your symptoms, list of medications you are taking, prior medical history, and reported symptoms of involuntary muscle contractions and movements observed by a family member or friend.
You may also have bloodwork and a computed tomography (CT) scan or magnetic resonance imaging (MRI) of your brain performed in order to rule out other conditions—such as a stroke, Parkinson’s disease, Huntington’s disease, cerebral palsy, or a brain tumor—which can also cause abnormal movements.
Treatment
Tardive Dyskinesia
Treatment for tardive dyskinesia usually begins with lowering medication dosage to see if symptoms decrease. If a lowered mediation dosage is ineffective, a type of medication called vesicular monoamine transporter 2 (VMAT2) inhibitors, such as valbenazine or deutetrabenazine, will be prescribed to decrease involuntary movements.
The protein VMAT2 controls transportation and release of neurotransmitters from nerve cells to muscles. VMAT2 inhibitors block the activity of this protein, which can help decrease nerve signaling to muscles and reduce excessive involuntary movements.
If VMAT2 inhibitors fail to reduce the symptoms of tardive dyskinesia, clonazepam, a benzodiazepine used to treat seizures, or ginkgo biloba, a plant extract from the leaves of ginkgo trees, may be prescribed to help decrease symptoms.
Dystonia
Treatment for dystonia most commonly involves taking anticholinergic medications, which block the action of the neurotransmitter acetylcholine, to reduce involuntary movements. If anticholinergic medications are ineffective for decreasing the symptoms of dystonia, antihistamines or benzodiazepines may be prescribed to help manage symptoms.
Other treatment methods for dystonia include injections of Botulinum neurotoxin (Botox) into contracted muscles to decrease pain and tightness.
Another treatment is deep brain stimulation to an area of the brain called the internal globus pallidus, which regulates voluntary movement and causes movement disorders when damaged. Electrodes will be surgically implanted into your brain to send electrical impulses to help regulate muscle control.
Prevention
Because symptoms of tardive dyskinesia and dystonia can be debilitating and sometimes permanent, proper prescription and dosing of medication is key to preventing these conditions.
Antipsychotic medications should only be prescribed if their use is clearly indicated and will benefit the patient. Antipsychotic medications should always be prescribed at the lowest effective dose, and as soon as symptoms of tardive dyskinesia or dystonia appear, the dose should be lowered if possible.
If a patient is already on the lowest available dose and symptoms are still present, the type of antipsychotic medication may be changed. If there is no benefit in taking an antipsychotic medication, the medication will be discontinued.
For the prevention of dystonia, an anticholinergic medication is most often prescribed along with antipsychotic medication to help prevent negative side effects.
Summary
Tardive dyskinesia and dystonia are both movement disorders that result from taking antipsychotic medications. Tardive dyskinesia causes involuntary movements most commonly in areas of the face, eyes, and mouth. Dystonia, on the other hand, leads to involuntary muscular contractions that can affect the head, face, and neck.
Unlike tardive dyskinesia, dystonia can also be caused by infections, tumors, exposure to toxins, and brain injury. The best way to treat and prevent both conditions is to reduce the dosage of the medication that’s causing symptoms or to change the medication entirely.
A Word From Verywell
While antipsychotic medication is often necessary and very beneficial for managing the symptoms of schizophrenia and other mental disorders, it can cause negative side effects like involuntary movements. It’s important that your doctor supervises you regularly while you are taking this medication to screen for movement abnormalities.
If you are experiencing any negative side effects from your medication, you should tell your doctor immediately so that your type of medication or dosage can be adjusted to help minimize side effects. If changes to your medication cannot be made, other types of medication may be prescribed to help manage the side effects.
