以Gabapentin成功治療傳統抗癲癇藥物療效不佳的三叉神經痛－－病例報告

Refractory Trigeminal Neuralgia Successfully Treated with Gabapentin -A Case Report

三叉神經捕的治療在臨床上有很高的困難度。第一線的治療以傳統的抗癲癇藥物（carbamazepine, phenytoin）為主，但療效不佳和藥物的神經性副作用是常見的問題。我們報告一位42歲患有三叉神經痛的男性，在傳統的抗癥痛藥物（carbamazepine, phenytoin）治療下，三叉神經痛仍然持續發作。核磁共振檢查發現右側的三叉神經根被腫瘤壓迫，所以這是一個次發性的三叉神經痛病例。在安排放射治療的同時，不同種類的抗癲癇藥物（phenytoin, clonazepam, mexiletine）也曾被使用，但治療的效果不佳，病人的三叉神經痛仍持續發作。由於已有臨床報告顯示gabapentin在三叉神經痛和其他神經病變疼痛的治療上具有療效，所以我們給予病患口服一天三次gabapentin300呵，在3天後，三叉神經痛的發作顯著消失，觸感痛、刺痛及燃燒痛都得到改善，經過三個月的追蹤，三叉神經痛仍然得到有效的控制。因此對於傳統抗癥痛藥物治療效果不佳的頑固性三叉神經痛，我們認為gabapentin可提供另一種的藥物治療選擇。

Carbamazepine and its related anticonvulsants are the treatment of choice for trigeminal neuralgia for many years. But trigeminal neuralgia refractory to conventional anticonvulsant agents is still the main challenge to clinicians. We report a 42 - year-old male who was a victim oftrigeminal neuralgia for four years. Beside, he had undergone craniotomy and radiotherapy for right middle fossa meningioma five years ago. In general, his pain could be controlled by carbamazepine and baclofen. But the frequency and duration of the attack became severe despite the medical treatment. He described the pain sensation as sharp, stabbing and burning and it could be triggered by touch, shaving or chewing. Secondary trigeminal neuralgia was diagnosed because brain MRI examination revealed right trigeminal nerve root compression by a right parasellar area recurrent tumor. The neurologist had adjusted the medications to other traditional anticonvulsants but the pain was not resolved. The patient even tried not to eat or drink to avoid triggering the attack. Since the right internal carotid artery was involved and the risk of surgical treatment was high, radiotherapy was arranged. At the same time, we were consulted for neurolytic block. Considering the risk of the procedure, we suggested the use of gabapentin, a novel anticonvulsant and analgesic. Fortunately, the pain was relieved after one-week treatment of gabapentin and did not attack again during the 3 months follow-up. We present this case to offer another therapeutic option for trigeminal neuralgia that is refractory to traditional anticonvulsant drugs.