Adjunctive 810 nm photobiomodulation with pharmacotherapy for trigeminal neuralgia: A randomized controlled trial in a tertiary care centre.

Background: Trigeminal neuralgia (TN) is a debilitating orofacial pain disorder. Pharmacotherapy with carbamazepine is the mainstay of treatment, but adverse effects and tolerance often limit its long-term use. Low-level laser therapy (LLLT) has shown promise in managing various neuropathic pains, yet no study has assessed its efficacy as an adjunct in TN treatment within an Indian population.

Methods: In this single-center randomized controlled trial, 40 patients with classical TN were randomly allocated into two groups: Group I received carbamazepine alone, and Group II received carbamazepine plus LLLT (using an 810 nm diode laser at 200 mW for 30s per point). Pain intensity was assessed using the Numeric Rating Scale (NRS) at baseline, 1, 2, and 3 weeks, and the McGill Pain Questionnaire at baseline and after 3 months. LLLT was administered thrice weekly for 3 weeks at 810 nm, delivering 6 J per irradiation point. Outcomes were evaluated by a blinded assessor.

Results: Baseline NRS scores were similar (8.50 ± 0.95 vs. 8.75 ± 0.96, p = 0.412). At 3 weeks, mean NRS reduced significantly more in Group II (0.40 ± 0.68) than Group I (3.45 ± 1.23), p < 0.001. McGill scores at 3 months were significantly lower in Group II (2.90 ± 3.07) compared to Group I (23.40 ± 6.38), p < 0.001. None in Group II required carbamazepine dose escalation during the study, whereas all patients in Group I needed increases.

Conclusion: Combined photobiomodulation with carbamazepine provided significantly superior pain relief compared to medication alone in TN patients, reducing the need for higher drug doses. This is the first study to demonstrate the benefits of LLLT as an adjunct therapy in TN among the Indian population, indicating it as a promising option for adjunctive management.