Understanding Tardive Dyskinesia and the Medications Used to Treat It
Tardive dyskinesia (TD) is a neurological disorder characterized by involuntary, repetitive movements, most commonly affecting the face, mouth, tongue, and sometimes the limbs or torso. It is often associated with the long-term use of antipsychotic medications, especially first-generation or "typical" antipsychotics. While the exact cause of TD is not fully understood, it is believed to result from an imbalance of neurotransmitters, particularly dopamine, in the brain.
Though TD can be distressing and have a significant impact on a person's quality of life, advances in medicine have led to the development of treatments to manage or even alleviate the condition. In this blog post, we will explore the causes of tardive dyskinesia, its symptoms, and the medications used to treat it.
What is Tardive Dyskinesia?
Tardive dyskinesia is typically a side effect of long-term use of certain medications, especially antipsychotic drugs. While these medications can be effective in managing psychiatric conditions such as schizophrenia, bipolar disorder, and depression, prolonged use can lead to motor disturbances such as:
Involuntary facial movements: Tongue protrusion, lip smacking, puckering, or grimacing.
Body movements: Twitching or jerking of the limbs, trunk, or torso, and sometimes more complex movements like rocking or swaying.
Speech impairments: Difficulty articulating words due to uncontrollable movements of the mouth or tongue.
TD typically develops after months or years of taking antipsychotic medications, and while it can occur in both first-generation (typical) and second-generation (atypical) antipsychotics, it is more common with older medications. Not all individuals who take antipsychotics will develop TD, and some people are at higher risk due to genetic or environmental factors.
How Does Tardive Dyskinesia Develop?
The condition is thought to arise from the dopamine receptors in the brain becoming hypersensitive over time due to the prolonged use of antipsychotic medications. These drugs primarily work by blocking dopamine receptors to control symptoms of psychosis, but over time, the brain may adapt by increasing the number of dopamine receptors. When the medication is withdrawn or changed, these overactive receptors can cause involuntary movements.
TD can sometimes develop even after the antipsychotic medication has been discontinued, and in many cases, it can be permanent. However, earlier detection and treatment can improve outcomes and reduce the severity of symptoms.
Medications for Treating Tardive Dyskinesia
Fortunately, there are medications that can help manage the symptoms of TD, some of which specifically target the underlying causes of the condition. These treatments can be classified into two main categories: dopamine-depleting agents and dopamine-receptor modulators. Let’s take a closer look at some of the most common medications used to treat TD.
1. Valbenazine (Ingrezza)
Valbenazine, marketed under the brand name Ingrezza, is a medication approved by the FDA specifically for the treatment of tardive dyskinesia. It works by selectively inhibiting the vesicular monoamine transporter 2 (VMAT2), a protein responsible for transporting dopamine and other neurotransmitters into nerve cells. By reducing the release of dopamine in the brain, valbenazine helps reduce the involuntary movements associated with TD.
How It Works: Valbenazine reduces dopamine signaling, which helps to normalize motor control and alleviate the movements caused by TD. It’s a targeted approach, meaning it works on the specific receptors involved in the condition.
Benefits: Valbenazine has been shown to significantly reduce the severity of TD symptoms, with studies demonstrating improvements in both motor and non-motor symptoms. It’s generally well-tolerated, with side effects being mild and infrequent, including sleepiness and fatigue.
Considerations: The medication needs to be taken daily, and while it can significantly improve symptoms, it does not cure TD. Regular monitoring by a healthcare provider is necessary.
2. Deutetrabenazine (Austedo)
Deutetrabenazine, sold under the brand name Austedo, is another FDA-approved treatment for tardive dyskinesia. It is a derivative of tetrabenazine, a drug previously used to treat movement disorders like Huntington's disease, and it works by similarly reducing the amount of dopamine available in the brain.
How It Works: Deutetrabenazine inhibits the VMAT2 protein, similar to valbenazine. This reduces the excessive release of dopamine, which helps in controlling the involuntary movements associated with TD.
Benefits: Austedo has been shown to be effective in reducing the symptoms of tardive dyskinesia, with improvements noted in both voluntary and involuntary motor control. It has a slower elimination rate compared to tetrabenazine, which may result in fewer side effects.
Considerations: Common side effects of deutetrabenazine include sleepiness, fatigue, and depression. As with all medications, a healthcare provider will need to closely monitor for potential side effects and adjust the dose as needed.
Conclusion: Managing Tardive Dyskinesia
Tardive dyskinesia can be a challenging condition to live with, especially as it often occurs after prolonged use of antipsychotic medications. However, with the development of targeted treatments like valbenazine and deutetrabenazine, there are now more options available to manage the symptoms and improve quality of life.
If you or someone you know is experiencing involuntary movements that could be a sign of tardive dyskinesia, it’s important to consult with a healthcare provider as soon as possible. Early detection and intervention are key to minimizing the severity of symptoms and finding the right treatment plan. While there is currently no cure for TD, advancements in treatment options offer hope for better management of the condition.
With the right combination of medication, lifestyle adjustments, and ongoing monitoring, individuals with tardive dyskinesia can continue to lead fulfilling lives.
