Moderate
Amitriptyline × Gabapentin
Tricyclic antidepressants (TCA)×Gabapentinoids (antiepileptics)
Mechanism
Additive CNS depression via different mechanisms. Sedation, dizziness, and fall risk amplify, especially in older patients.
Symptoms
Sedation, fatigue, slowed reactions, impaired coordination. In older patients: fall and fracture risk. Driving and operating machinery: accident risk.
Management
For neuropathic pain (diabetic neuropathy, post-herpetic neuralgia), start both at minimum doses: amitriptyline 10 mg at bedtime, gabapentin 100 mg three times daily. Up-titrate every 1–2 weeks as tolerated. Avoid in older patients — fall risk. Alternatives: duloxetine with topicals (capsaicin, lidocaine patch).
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.