Non-antiepileptic drugs for trigeminal neuralgia.
BACKGROUND
Non-antiepileptic drugs have been used in the management of trigeminal neuralgia since the 1970s.


OBJECTIVE
The objective was to systematically review the efficacy and tolerability of non-antiepileptic drugs for trigeminal neuralgia.


METHODS
For this updated review we searched the Cochrane Neuromuscular Disease Group Specialized Register (30 April 2010). We also searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 2), MEDLINE (January 1966 to April 2010), EMBASE (January 1980 to April 2010), LILACS (January 1982 to April 2010) and the Chinese Biomedical Retrieval System (1978 to April 2010). We handsearched 10 Chinese journals.


METHODS
We searched for double-blind randomized or quasi-randomized controlled trials in which the active drug was used for at least two weeks.


METHODS
Two authors decided which trials fitted the inclusion criteria and independently graded risk of bias.


RESULTS
Four trials involving 139 participants were included. The primary outcome measure in each was pain relief. Three trials with an unclear risk of bias compared one of the non-antiepileptic drugs tizanidine, tocainide or pimozide with carbamazepine. In a trial of tizanidine involving 12 participants (one dropped out due to unrelated disease) one of five treated with tizanidine and four of six treated with carbamazepine improved, risk ratio 0.30 (95% CI 0.05 to 1.89). Few side effects were noted with tizanidine. In a study involving 12 participants there was an improvement in mean pain scores with tocainide similar to that with carbamazepine, but significant side effects limited its use. In the pimozide study more participants improved on pimozide (48/48) than with carbamazepine (27/48) (risk ratio 1.76, 95% CI 1.37 to 2.26). Up to 83% of participants reported adverse effects but these did not lead to withdrawal from the study. A trial with low risk of bias involving 47 participants compared 0.5% proparacaine hydrochloride eyedrops with placebo but did not show any significant benefits or side effects.


CONCLUSIONS
Of the four studies identified, one had low and three an unclear risk of bias. There is insufficient evidence from randomized controlled trials to show significant benefit from non-antiepileptic drugs in trigeminal neuralgia. More research is needed.
Department of Neurology, West China Hospital, Sichuan University, No. 37, Guo Xue Xiang, Chengdu, Sichuan, China, 610041.
Mi
M
Yang
Muke
M
Zhou
Li
L
He
Ning
N
Chen
Joanna M
JM
Zakrzewska
D000639:Amitriptyline / Q000627:therapeutic use; D000700:Analgesics / Q000627:therapeutic use*; D001418:Baclofen / Q000627:therapeutic use; D002220:Carbamazepine / Q000627:therapeutic use; D002997:Clomipramine / Q000627:therapeutic use; D003000:Clonidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D006801:Humans; D010868:Pimozide / Q000627:therapeutic use; D011430:Propoxycaine / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D016677:Tocainide / Q000627:therapeutic use; D014277:Trigeminal Neuralgia / Q000188:drug therapy*
D000700:Analgesics; D000639:Amitriptyline; D010868:Pimozide; D016677:Tocainide; D002220:Carbamazepine; D011430:Propoxycaine; D001418:Baclofen; D003000:Clonidine; D002997:Clomipramine