Article type
Year
Abstract
Background: Non-antiepileptic drugs have been used in trigeminal neuralgia management since the 1970s. Drugs used include baclofen, pimozide, tizanidine, proparacaine and tocainide. A number of randomized controlled trials of non-antiepileptic drugs for treating trigeminal neuralgia have been published. There is no known systematic review of non-antiepileptic drug treatment for trigeminal neuralgia.
Objectives: The objective of this review was to examine the efficacy of non-antiepileptic drugs to treat trigeminal neuralgia. Methods: We searched the Cochrane Neuromuscular Disease Group register for randomized or quasi-randomized controlled trials. We also searched MEDLINE, EMBASE, LILACS, the Chinese Biomedical Retrieval System, the RCT, CCT Database of Chinese EBM/ Cochrane Center and conference paper databases. We searched ten journals by hand. The primary outcome measure was the proportion of patients with a good initial effect one to eight weeks after treatment; the secondary outcome measures were the number of patients with a good long-term effect at least twelve weeks after treatment and the number of patients reporting adverse effects. Two reviewers decided which trials fit the inclusion criteria and graded their methodological quality independently. Information was collected from each study. Results were expressed as relative risk (RRs) with 95% confidence intervals for dichotomous outcomes.
Results: Nine trials were eligible for our study. Only one trial observed the number of patients with a good long-term effect. Four trials recorded adverse effects. We found that baclofen significantly relieved trigeminal neuralgia when compared to placebo. When compared with carbamazepine, there was only a tendency to increase the proportion of people with relief of pain. Although there was no significant difference in the number of patients with pain relief when treated with L-Baclofen compared with racemic baclofen, L-Baclofen produced a significant decrease in the number of attacks of trigeminal neuralgia. The adverse effects with L-Baclofen were also less than those with racemic baclofen. Tizanidine increased the number of patients who improved in pain significantly compared with placebo. But the tendency indicated that the effect of tizanidine was worse than that of carbamazepine. Tocainide had a similar effect as carbamazepine, but the serious side effects restricted its clinical use. Proparacaine hydrochloride 0.5% instillation into the eyes was simple, but no significant effect was apparent when compared with placebo. Pimozide was better in controlling pain than cabamazepine, but adverse effects were common. Only one trial reported the long-term effect of non-antiepileptic drugs. This trial indicated that clomipramine was more effective than amitriptyline in tendency.
Conclusions: This review indicates that trials of non-antiepileptic drugs for trigeminal neuralgia are limited by poor methodological quality. No sufficient evidence certifies the efficacy of non-antiepileptic drugs at present. We have no evidence to recommend these non-antiepileptic drugs as routine therapeutics for trigeminal neuralgia. But some drugs such as baclofen, pimozide, tocainide, chlorimipramine have potential. It is necessary to carry out high quality and large sample size RCTs to further ascertain the effect of these drugs. Future trials should improve their design. Measurement tools such as VAS, NRS, VRS, which have good reliability and validity, should be used to assess pain.
Objectives: The objective of this review was to examine the efficacy of non-antiepileptic drugs to treat trigeminal neuralgia. Methods: We searched the Cochrane Neuromuscular Disease Group register for randomized or quasi-randomized controlled trials. We also searched MEDLINE, EMBASE, LILACS, the Chinese Biomedical Retrieval System, the RCT, CCT Database of Chinese EBM/ Cochrane Center and conference paper databases. We searched ten journals by hand. The primary outcome measure was the proportion of patients with a good initial effect one to eight weeks after treatment; the secondary outcome measures were the number of patients with a good long-term effect at least twelve weeks after treatment and the number of patients reporting adverse effects. Two reviewers decided which trials fit the inclusion criteria and graded their methodological quality independently. Information was collected from each study. Results were expressed as relative risk (RRs) with 95% confidence intervals for dichotomous outcomes.
Results: Nine trials were eligible for our study. Only one trial observed the number of patients with a good long-term effect. Four trials recorded adverse effects. We found that baclofen significantly relieved trigeminal neuralgia when compared to placebo. When compared with carbamazepine, there was only a tendency to increase the proportion of people with relief of pain. Although there was no significant difference in the number of patients with pain relief when treated with L-Baclofen compared with racemic baclofen, L-Baclofen produced a significant decrease in the number of attacks of trigeminal neuralgia. The adverse effects with L-Baclofen were also less than those with racemic baclofen. Tizanidine increased the number of patients who improved in pain significantly compared with placebo. But the tendency indicated that the effect of tizanidine was worse than that of carbamazepine. Tocainide had a similar effect as carbamazepine, but the serious side effects restricted its clinical use. Proparacaine hydrochloride 0.5% instillation into the eyes was simple, but no significant effect was apparent when compared with placebo. Pimozide was better in controlling pain than cabamazepine, but adverse effects were common. Only one trial reported the long-term effect of non-antiepileptic drugs. This trial indicated that clomipramine was more effective than amitriptyline in tendency.
Conclusions: This review indicates that trials of non-antiepileptic drugs for trigeminal neuralgia are limited by poor methodological quality. No sufficient evidence certifies the efficacy of non-antiepileptic drugs at present. We have no evidence to recommend these non-antiepileptic drugs as routine therapeutics for trigeminal neuralgia. But some drugs such as baclofen, pimozide, tocainide, chlorimipramine have potential. It is necessary to carry out high quality and large sample size RCTs to further ascertain the effect of these drugs. Future trials should improve their design. Measurement tools such as VAS, NRS, VRS, which have good reliability and validity, should be used to assess pain.