Medications That Cause Diffuse Tremors
The most common medications causing diffuse tremor include beta-agonists (albuterol, salmeterol), SSRIs/SNRIs, lithium, valproate, amiodarone, tricyclic antidepressants, and drugs of abuse such as cocaine and amphetamines. 1, 2
Psychiatric Medications
Antidepressants
- SSRIs (selective serotonin reuptake inhibitors) commonly cause dose-related tremor as a class effect, with sweating and nervousness also reported 1
- SNRIs including duloxetine, venlafaxine, desvenlafaxine, and levomilnacipran cause tremor through serotonergic mechanisms and may have higher discontinuation rates than SSRIs 1
- Tricyclic antidepressants (amitriptyline, desipramine, nortriptyline, doxepin, imipramine) cause tremor through central mechanisms affecting physiological tremor 1, 2
- Bupropion can cause tremor and requires caution in seizure-prone patients 1
- Mirtazapine may cause tremor despite generally good tolerability 1
Mood Stabilizers
- Lithium causes tremor, particularly in elderly patients who are prone to neurotoxicity at higher doses (therapeutic levels of 0.2-0.6 mEq/L are adequate in older adults) 1, 2
- Valproate is a well-recognized cause of tremor 2
- Lamotrigine induces tremor in approximately 10% of patients on monotherapy, though with lower incidence than typical antipsychotics 3
Antipsychotics
- Dopamine receptor antagonists cause tremor, with aripiprazole showing clear dose-dependent increases 3, 2
- VMAT2 inhibitors are associated with tremor 2
Other Psychotropic Agents
- MAO inhibitors (phenelzine, isocarboxazid, selegiline, linezolid, tranylcypromine) carry tremor risk and serious interaction potential with serotonergic drugs 1
Cardiovascular Medications
- Beta-agonists (albuterol, salmeterol, terbutaline) cause tremor through peripheral β-adrenergic receptor stimulation in muscle, representing classic enhancement of physiological tremor 4, 1
- Amiodarone is associated with tremor despite its paradoxically low risk for torsades de pointes 2
Sympathomimetic Agents
- Cocaine and amphetamines cause fine tremor, tachycardia, and sweating through sympathomimetic stimulation 4
- Ephedra alkaloids (including "ma huang") cause tremor through direct myocardial sympathomimetic stimulation 4
- Decongestants and anorectics containing sympathomimetics cause tremor 4
Pain Medications
- Opioids including tramadol, meperidine, methadone, and fentanyl can cause tremor, with particular concern when combined with serotonergic medications due to serotonin syndrome risk 1
Substances of Abuse
- Caffeine is a well-recognized cause of tremor 5
- Nicotine (smoking) causes tremor 4
- Alcohol causes tremor both during intoxication and withdrawal 4, 2
- Cocaine causes tremor through multiple mechanisms including sodium channel blockade and sympathomimetic effects 4, 2
Other Medications
- Cyclosporine and tacrolimus (immunosuppressants) cause tremor 4
- Erythropoiesis-stimulating agents are associated with tremor 4
- Clonidine withdrawal can precipitate tremor 4
Clinical Risk Factors
- Polypharmacy, male gender, older age, high doses, and immediate-release preparations increase risk for drug-induced tremor 2
- Approximately 63% of patients on second-generation antidepressants experience at least one adverse effect, with tremor commonly reported 1
- Combining multiple serotonergic drugs requires careful monitoring, with particular vigilance in the first 24-48 hours after dosage changes 1
Management Considerations
- Drug-induced tremor usually resolves once the offending medication is discontinued, though persistent tremor (tardive tremor) may occur in some cases 2
- When SSRI-induced tremor occurs early in treatment or with dose increases, consider dose reduction or slower up-titration 1
- Never abruptly discontinue medications without appropriate tapering and alternative treatment planning 3
- Distinguish between benign drug-induced tremor and serotonin syndrome, which requires immediate hospitalization and discontinuation of all serotonergic agents 1