What Drug Makes You Twitch and Jerk? A Review of Medication-Induced Movement Disorders

October 5, 2025 •

3 min read

Tardive dyskinesia, a specific drug-induced movement disorder, affects over 500,000 people in the United States alone. The answer to 'What drug makes you twitch and jerk?' is complex, as numerous medications can cause these involuntary movements, known as myoclonus, as a side effect.

Quick Summary

A wide range of medications, from antidepressants and antipsychotics to stimulants and antibiotics, can cause involuntary muscle twitching and jerking. These movements are often a symptom of conditions like myoclonus, tardive dyskinesia, or serotonin syndrome.

Key Points

Many Drug Classes are Culprits: Involuntary twitching and jerking (myoclonus) can be caused by antidepressants, antipsychotics, opioids, stimulants, antibiotics, and anticonvulsants.
Tardive Dyskinesia is a Delayed Disorder: TD involves repetitive movements, often of the face, and is a delayed side effect of long-term use of dopamine-blocking drugs like antipsychotics.
Serotonin Syndrome is an Acute Risk: An excess of serotonin from medications like SSRIs can cause rapid onset of twitching, agitation, fever, and high heart rate.
Neurotransmitter Imbalance is Key: Most drug-induced movements are caused by disruption of neurotransmitters like dopamine, serotonin, and GABA in the brain.
Never Stop Medication Abruptly: If you experience twitching, consult a doctor. Suddenly stopping a medication can be dangerous and may worsen symptoms.
Antipsychotics Carry High Risk: First-generation antipsychotics are most strongly linked to tardive dyskinesia, affecting an estimated 20% of patients on these older drugs.
Common Antiemetics Are Risky: The anti-nausea drug metoclopramide (Reglan) carries a significant risk of causing tardive dyskinesia.

Understanding Drug-Induced Involuntary Movements

Involuntary muscle movements, from minor twitches to severe jerks, can be a side effect of various medications. These movements are often categorized as myoclonus or dyskinesia. Myoclonus refers to sudden, brief muscle contractions (positive) or relaxations (negative). While common in healthy people (like hiccups), myoclonus can also be a sign of a drug reaction.

Tardive Dyskinesia (TD) is a well-known drug-induced movement disorder, with symptoms often appearing months or years after starting a medication. TD involves uncontrollable, repetitive movements, frequently in the face, mouth, and tongue. It's primarily linked to long-term use of antipsychotics, though other drugs can also be responsible.

The Pharmacology: Why Do Drugs Cause Twitching?

Drug-induced movements are complex and involve neurotransmitters. Many drugs that cause these movements block dopamine receptors in the brain. The leading theory for TD is that long-term dopamine blockage increases the sensitivity of these receptors, causing involuntary movements.

Other neurotransmitters are also involved:

Serotonin: High levels, often from combining certain medications, can lead to serotonin syndrome. Myoclonus, tremor, and hyperreflexia are key features.
GABA: Damage to GABA-producing neurons may contribute to TD.
Acetylcholine: An imbalance with dopamine is thought to play a role in TD.

Common Classes of Drugs That Cause Twitching and Jerking

Many medications can cause myoclonus or other involuntary movements.

Antipsychotics

Antipsychotics are strongly associated with movement disorders. First-generation antipsychotics have a higher risk of causing tardive dyskinesia than second-generation ones. About 20% of those on older antipsychotics may develop TD.

Antidepressants

Several antidepressants are linked to twitching and jerking:

SSRIs and SNRIs: Medications like fluoxetine and sertraline can cause myoclonus. They are also common causes of serotonin syndrome.
Tricyclic Antidepressants (TCAs): Amitriptyline and clomipramine can induce myoclonus and TD.
MAOIs: These are linked to TD and have a high risk of serotonin syndrome when combined with other drugs.

Stimulants

ADHD medications such as methylphenidate and amphetamines can cause muscle twitching. They can also cause muscle pain and stiffness. Combining stimulants with antidepressants increases serotonin syndrome risk.

Other Notable Drug Classes

Opioids: Tramadol, morphine, and fentanyl are often associated with drug-induced myoclonus.
Anticonvulsants: Ironically, some seizure medications like gabapentin and valproic acid can cause myoclonus.
Antibiotics: Certain antibiotics, including penicillins and cephalosporins, can cause a neurotoxic syndrome with myoclonus, especially with kidney problems.
Antiemetics: Anti-nausea drugs like metoclopramide carry a significant TD risk due to blocking dopamine.

Comparison of Common Drug-Induced Movement Disorders


Feature	Myoclonus	Tardive Dyskinesia (TD)	Serotonin Syndrome
Movement Type	Brief, sudden, shock-like jerks or twitches	Repetitive, involuntary, writhing or jerking movements (e.g., lip-smacking, grimacing)	Myoclonus (twitching), tremor, muscle rigidity, overactive reflexes
Common Drug Causes	Opioids, antidepressants, antibiotics, anticonvulsants	Antipsychotics (especially 1st gen), metoclopramide, some antidepressants	SSRIs/SNRIs, MAOIs, TCAs, tramadol, often in combination
Onset	Can be rapid, occurring soon after starting or increasing a dose	Delayed ("tardive"), appearing months to years after starting a drug	Rapid, usually within hours to a day of a dose change or new drug
Accompanying Symptoms	Often an isolated neurological sign	Primarily a movement disorder, can be accompanied by restlessness (akathisia)	Agitation, confusion, high heart rate, sweating, fever, diarrhea

What to Do If You Experience Medication-Induced Twitching

If you experience involuntary twitching or jerking while on medication, contact your healthcare provider promptly. Do not stop taking any prescribed medication abruptly, as this can worsen symptoms or cause withdrawal.

A doctor can determine the cause by:

Reviewing your medications and supplements.
Performing a neurological exam.
Adjusting the drug dosage, switching to an alternative, or prescribing medication to manage symptoms.

Conclusion

Many common medications, not just one, can cause twitching and jerking by affecting brain chemistry. Antipsychotics, antidepressants, stimulants, and antibiotics are among the culprits, leading to conditions like myoclonus, tardive dyskinesia, and serotonin syndrome. Recognizing these symptoms and risky medications is important. The most crucial step is to seek medical advice for diagnosis and management. For more information on myoclonus, consult the National Institute of Neurological Disorders and Stroke (NINDS).

Frequently Asked Questions

In some cases, yes. While many forms of drug-induced myoclonus are reversible upon withdrawing the drug, tardive dyskinesia can be permanent for some individuals, even after the medication is stopped.

Myoclonus involves brief muscle jerks without a loss of consciousness and is considered a symptom, not a disease itself. Seizures are caused by abnormal electrical activity in the brain and can involve a wider range of symptoms, including altered consciousness. However, myoclonic seizures are a feature of some epilepsy syndromes.

It varies. Symptoms of serotonin syndrome can begin within hours of taking a new drug or increasing a dose. Tardive dyskinesia is typically delayed, appearing after months or years, though it can occur in as little as six weeks in some cases.

Yes. Some decongestants and antihistamines have been associated with drug-induced movement disorders. Combining certain OTC products, like those containing dextromethorphan, with prescription antidepressants can also trigger serotonin syndrome.

Tardive dyskinesia is a movement disorder characterized by delayed, involuntary, and repetitive movements of the face, limbs, and trunk. It is most commonly caused by long-term use of antipsychotic medications.

Serotonin syndrome is a potentially life-threatening condition caused by excessive levels of serotonin in the body. Symptoms include high body temperature, agitation, increased reflexes, tremor, sweating, and muscle twitching (myoclonus).

You should see a doctor promptly if you experience new or worsening muscle twitching, especially after starting a new medication or changing a dose. It is particularly urgent if the twitching is accompanied by other symptoms like confusion, high fever, or severe stiffness.