Agomelatine Does Not Cause Jaw Clenching Like SSRIs
Agomelatine is unlikely to cause jaw clenching (bruxism) because it works through a completely different mechanism than SSRIs—it acts on melatonin receptors rather than serotonin reuptake—and this side effect has not been reported in its clinical profile.
Why SSRIs Cause Bruxism
SSRIs are well-documented to cause bruxism as a common adverse effect. Multiple clinical practice guidelines explicitly list bruxism among SSRI side effects 1. Recent large-scale studies confirm this association:
- A 2026 electronic health record analysis of 14,643 patients found that serotonin-norepinephrine reuptake inhibitors (SNRIs) showed significantly elevated odds of tooth clenching (adjusted OR 1.24), and CNS polypharmacy involving multiple serotonergic drugs increased risk progressively 2
- Another 2026 study of 583 patients found that SSRI/SNRI users were 2.5 times more likely to present with bruxism compared to non-users (OR 2.52; 95% CI: 1.21-5.23) 3
- The combination of SSRI plus SNRI showed particularly strong association (OR 2.40) 2
The mechanism relates to excess serotonergic activity affecting jaw muscle control and motor function.
Agomelatine's Different Mechanism
Agomelatine has a fundamentally different pharmacological profile. It is a melatonin receptor agonist (MT1 and MT2) with 5-HT2C antagonist properties—it does not inhibit serotonin reuptake 4, 5. This unique mechanism means it avoids the typical serotonergic side effects.
Clinical studies consistently demonstrate agomelatine's favorable side effect profile:
- Agomelatine does not induce gastrointestinal disorders, weight gain, serotonin syndrome, or insomnia typical of SSRIs 4
- It showed significantly lower discontinuation rates due to side effects compared to SSRIs/SNRIs (RR 0.38; 95% CI 0.25-0.57) 5
- A meta-analysis of 1,871 patients found agomelatine had better tolerability than SSRIs/SNRIs 5
Clinical Bottom Line
Bruxism is not listed among agomelatine's documented adverse effects in any of the available clinical literature 4, 6, 7, 5. The drug's melatonergic mechanism avoids the serotonergic pathway implicated in SSRI-induced bruxism.
Important Caveats
- Agomelatine requires liver function monitoring due to potential hepatotoxicity—check transaminases at baseline, 3,6,12, and 24 weeks 6, 8
- It is approved in Europe and Australia but not FDA-approved in the United States 6
- While it avoids bruxism, agomelatine can cause dizziness, gastrointestinal symptoms, and cutaneous disorders 8
If a patient develops bruxism on an SSRI and requires antidepressant therapy, agomelatine represents a mechanistically distinct alternative that should not perpetuate this side effect, though availability depends on geographic location.