From the Guidelines
Duloxetine can cause tremor as a side effect, as evidenced by the clinical practice guideline for the assessment and treatment of children and adolescents with anxiety disorders published in the Journal of the American Academy of Child and Adolescent Psychiatry in 2020 1. Tremors associated with duloxetine are considered a relatively common adverse reaction to this medication.
- The tremors typically present as involuntary, rhythmic muscle movements and are usually mild to moderate in severity.
- They may be more noticeable in the hands and occur because duloxetine increases levels of serotonin and norepinephrine in the brain, affecting motor control pathways. If you experience tremors while taking duloxetine, you should report this to your healthcare provider, especially if they are severe or interfering with daily activities.
- In many cases, tremors may diminish over time as your body adjusts to the medication.
- Your doctor might consider adjusting your dosage, switching to a different medication, or adding another medication to manage this side effect if it becomes problematic. Some strategies that may help reduce tremor severity include staying well-hydrated and avoiding caffeine. It is essential to weigh the benefits of duloxetine against the potential risks, including tremor, and discuss any concerns with your healthcare provider to determine the best course of treatment for your specific condition, as emphasized in the guideline 1.
From the FDA Drug Label
Other adverse reactions that occurred at an incidence of less than 2% and were reported by more duloxetine delayed-release capsules-treated patients than placebo-treated patients in pediatric MDD and GAD clinical trials included: abnormal dreams (including nightmare), anxiety, flushing (including hot flush), hyperhidrosis, palpitations, pulse increased, and tremor Reported clinical findings have included respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia, hypertonia, hyperreflexia, tremor, jitteriness, irritability, and constant crying.
Tremor is listed as an adverse reaction that occurred in pediatric MDD and GAD clinical trials, as well as a clinical finding in neonates exposed to duloxetine delayed-release capsules.
- Key points:
From the Research
Duloxetine and Tremor
- Duloxetine, a serotonin-norepinephrine reuptake inhibitor, has been associated with tremor in some studies 3, 4.
- In a study published in 1995, duloxetine was found to induce head movement behavior and tremor in mice and rats when administered simultaneously with 5-hydroxytryptophan, a precursor of serotonin 3.
- A case report published in 2025 described a patient who developed duloxetine-associated parkinsonism, which included symptoms such as resting tremor, dystonic posturing, and bradykinesia, after taking duloxetine for numbness in the left sole 4.
- Another study published in 2022 listed selective serotonin (and norepinephrine) reuptake inhibitors, such as duloxetine, as one of the most common drugs associated with tremor 5.
Mechanisms and Risk Factors
- The exact mechanisms of duloxetine-induced tremor are not fully understood, but potential mechanisms include inhibition of dopamine release due to 5-HT2 receptor activation, postoperative effects, drug hypersensitivity, or genetic phenotypes in serotonin receptors 4.
- Risk factors for drug-induced tremor, including duloxetine, may include polypharmacy, male gender, older age, high doses, and immediate-release preparations or reaching toxic levels of the offending drugs 5.
Clinical Implications
- Duloxetine-associated tremor may resolve once the medication is discontinued, but persistent tremor may be observed in some cases 4, 5.
- Clinicians should be aware of the potential risk of tremor associated with duloxetine and monitor patients for this side effect, especially those with a history of movement disorders or taking other medications that may increase the risk of tremor 4, 5.