Single-Dose Botulinum Toxin as Adjunctive Treatment for Trigeminal Neuralgia: A Pilot Study
Jorns TP, DDS, MDSc, PhD1,7, Ieamsuwantada T, DDS2, Puttakun P, DDS3, Tiamkao S, MD4,7,8, Kitkhuandee A, MD5,7, Noisombut R, DDS, PhD6
Affiliation : 1 Department of Oral Biomedical Science, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand 2 Department of Dental Public Health, Sirindhorn College of Public Health, Suphanburi, Thailand 3 Dental Department, Takradan Hospital, Srisawat, Kanchanaburi, Thailand 4 Department of Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 5 Department of Surgery, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 6 Department of Preventive Dentistry, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand 7 Neuroscience Research and Development Group, Khon Kaen University, Khon Kaen, Thailand 8 Integrated Epilepsy Research Group, Khon Kaen University, Khon Kaen, Thailand
Objective : To evaluate the efficacy and safety of a single dosage of botulinum toxin type A (BTX-A) injection as an add-on therapy in
patients suffering from trigeminal neuralgia (TN).
Materials and Methods : Thirteen classical TN patients were enrolled in a 7-week long prospective open-label pilot study. A single
dosage of BTX-A (25 U/1.5 mL) injection was extra orally and intradermally administered into the skin of the trigger area of TN pain.
The primary outcome measures were pain severity per day, assessed by numeric rating scale (NRS), pain attack frequency and
number of antiepileptic medications taken per day.
Results : A total of 8 patients (1 man and 7 women) completed the study and were all improved regarding severity and frequency
of pain attack. The Wilcoxon signed-rank test showed a significant difference in frequency of pain attack before injection and at 4
weeks and 6 weeks after injection (p<0.05). Paired t-test of pain severity showed significant difference (p<0.05) between severity
of pain before and after injection. Wilcoxon signed-rank test showed significant reduction in medication intake in all patients up to
the end of trial at 6 weeks follow-up (p<0.05). In one patient, pain was completely eradicated and there was no need for further
medication. BTX-A was generally well tolerated and there were no serious treatment-related adverse events.
Conclusion : The present study revealed a clinical benefit in efficacy and safety of the combination of single dosing of BTX-A and
pharmacotherapy for patients with TN.
Keywords : Trigeminal neuralgia, Botulinum toxin, Carbamazepine, Pain severity, Pain frequency
