Does Wellbutrin Worsen Bruxism?
Yes, Wellbutrin (bupropion) can cause or worsen bruxism, though this is an uncommon adverse effect that appears to be dose-dependent. The evidence shows bupropion can induce acute dystonia including jaw clenching, trismus, and temporomandibular joint symptoms, particularly when doses are increased 1.
Evidence from Clinical Reports
A documented case report demonstrates that bupropion SR caused bilateral trismus, neck stiffness, and TMJ subluxation when the dose was increased from 150 mg once daily to 150 mg twice daily 1. Critically, symptoms appeared within 24-48 hours of dose escalation and resolved when the dose was reduced back to 150 mg once daily. When the patient was rechallenged with the higher dose, the same jaw and neck symptoms recurred within 24-48 hours, establishing a clear dose-response relationship 1.
Mechanism and Clinical Context
The dystonic reactions—including bruxism, jaw clenching, and trismus—are thought to result from bupropion's effects on dopaminergic and serotonergic systems 1. Bupropion acts as a norepinephrine and dopamine reuptake inhibitor, and medication-induced focal dystonias typically present with head, neck, and jaw muscle spasms, occasionally including bruxism and TMJ syndrome 1.
Practical Clinical Guidance
If a patient on Wellbutrin develops or experiences worsening bruxism:
- Monitor timing carefully: Symptoms typically emerge within 24-48 hours of starting therapy or increasing the dose 1
- Consider dose reduction first: The case evidence shows symptoms resolved at lower doses (150 mg daily) while maintaining antidepressant efficacy 1
- Evaluate for other dystonic features: Look for neck stiffness, jaw muscle tightness, difficulty rotating the head, or TMJ pain/subluxation 1
- Rule out other causes: Ensure no concurrent medications that could contribute (the case report noted buspirone augmentation may have sensitized the patient initially) 1
Important Caveats
While bupropion-induced bruxism is documented, it remains relatively uncommon and likely underrecognized 1. The FDA drug label for Wellbutrin does not specifically list bruxism as a common adverse effect 2, though it does warn about seizure risk (which is relevant since bupropion lowers seizure threshold and should be avoided in patients with brain metastases or seizure disorders) 3.
The dystonic reaction appears to be dose-dependent and potentially reversible with dose adjustment rather than requiring complete discontinuation 1. This is clinically important because it allows continued treatment at a lower effective dose for many patients.
For patients with pre-existing bruxism, close monitoring during bupropion initiation and dose titration is warranted, with particular attention during the first 48 hours after any dose increase.