Abstract
Patient: A 56-year-old man complained of pain in the left upper and lower jaw and the left cheek on his first visit to our clinic. The pain was triggered by chewing or speaking and persisted for a few minutes. Magnetic resonance imaging(MRI) scans showed the left trigeminal nerve in contact with the artery and vein at the root entry zone of the nerve. We diagnosed left trigeminal neuralgia (the second and third branches) and prescribed carbamazepine (200 mg/day),and the pain was alleviated. However,a blood examination conducted 6 weeks after treatment initiation revealed hepatic insufficiency. Concurrently, the pain became more severe. Therefore, we prescribed gabapentin（400 mg/day）instead of increasing the carbamazepine dose;subsequently, the pain reduced and liver function normalized. Fourteen weeks after treatment initiation, gabapentin was replaced with pregabalin（150 mg/day）and keishikajyutsubuto（7.5 g/day）,and the patient showed further pain relief. After about 3 weeks,the patient showed drug eruption,and carbamazepine administration was stopped. Although the patient was receiving only pregabalin and keishikajyutsubuto, the pain did not aggravate and the drug eruption disappeared. After about 1 month, keishikajyutsubuto administration was stopped,and the pregabalin dose was increased gradually to 600 mg/day,thereby ensuring pain control. The patient experienced pain relief and the pregabalin dose was decreased gradually.
Seventeen months after treatment initiation, pregabalin administration was stopped,and his treatment was ended the next month.
Discussion: Hepatic insufficiency caused by pregabalin or keishikajyutsubuto is much less frequent than that caused by carbamazepine. Therefore,this drug combination may be useful for treatment of persistent trigeminal neuralgia associated with hepatic insufficiency.
Conclusion: The treatment of mainly using pregabalin is useful for pain control in cases of persistent trigeminal neuralgia associated with hepatic insufficiency.
