Can you take Sertraline (Selective Serotonin Reuptake Inhibitor) and Lamotrigine (Anticonvulsant) together?

Sertraline and Lamotrigine Combination: Safety and Considerations

Yes, sertraline (an SSRI) and lamotrigine (an anticonvulsant) can be taken together, but this combination requires careful monitoring due to potential drug interactions that may affect lamotrigine levels.

Drug Interaction Considerations

• Sertraline may increase lamotrigine blood levels through inhibition of glucuronidation, potentially leading to lamotrigine toxicity even when lamotrigine levels appear within the therapeutic range 1
• Case reports have documented that adding even low doses of sertraline (25mg) to lamotrigine therapy can double lamotrigine blood levels and cause toxicity symptoms 1
• Conversely, some studies suggest the interaction may not be clinically significant in all patients, with one retrospective study showing only slightly slower metabolism of lamotrigine when combined with sertraline 2

Potential Adverse Effects

• Lamotrigine toxicity symptoms may include mental status changes and delirium, which can occur even when lamotrigine levels are within what is normally considered the therapeutic range 3
• A case report documented mental status changes in a 65-year-old man treated with lamotrigine and valproic acid after sertraline was added to his medication regimen 3
• While lamotrigine is generally well-tolerated, it can occasionally cause psychiatric symptoms including psychotic episodes and hallucinations 4

Monitoring Recommendations

• Blood level monitoring is essential when combining these medications to determine therapeutic and toxic ranges 1
• Serial blood level measurements of lamotrigine are advised when adding or adjusting sertraline dosage 1
• Close clinical monitoring for symptoms of lamotrigine toxicity is necessary, especially during the initial combination period 3, 1

Clinical Management Strategy

• When adding sertraline to existing lamotrigine therapy:
  • Start with a low dose of sertraline 1
  • Increase doses slowly with careful monitoring 1
  • Watch for symptoms of lamotrigine toxicity such as dizziness, double vision, headache, ataxia, and mental status changes 3, 1
• When adding lamotrigine to existing sertraline therapy:
  • Consider starting with a lower lamotrigine dose than typically recommended 1
  • Titrate lamotrigine more gradually than usual 1
  • Monitor lamotrigine levels regularly during dose adjustments 1

Important Caveats

• The evidence regarding this specific drug interaction is somewhat mixed, with some studies showing significant interactions 1 and others showing minimal effects 2
• Individual patient factors may influence the extent of interaction between these medications 3, 1
• Normal lamotrigine levels do not rule out toxicity, as clinical symptoms may occur despite "therapeutic" blood levels 3

Common Pitfalls to Avoid

• Failing to monitor lamotrigine levels when adding or adjusting sertraline dosage 1
• Overlooking symptoms of lamotrigine toxicity due to "normal" blood levels 3
• Neglecting to consider this interaction when diagnosing new-onset neuropsychiatric symptoms in patients on both medications 3, 1