Carbamazepine for acute and chronic pain in adults

Abstract

Background Carbamazepine is used to treat chronic neuropathic pain. Objectives Evaluation of analgesic efficacy and adverse effects of carbamazepine for acute and chronic pain management (except headaches). Search methods Randomised controlled trials (RCTs) of carbamazepine in acute, chronic or cancer pain were identified, searching MEDLINE, EMBASE, SIGLE and Cochrane CENTRAL to June 2010, reference lists of retrieved papers, and reviews. Selection criteria RCTs reporting the analgesic effects of carbamazepine. Data collection and analysis Two authors independently extracted results and scored for quality. Numbers needed to treat to benefit (NNT) or harm (NNH) with 95% confidence intervals (CI) were calculated from dichotomous data for effectiveness, adverse effects and adverse event withdrawal. Issues of study quality, size, duration, and outcomes were examined. Main results Fifteen included studies (12 cross-over design; three parallel-group) with 629 participants. Carbamazepine was less effective than prednisolone in preventing postherpetic neuralgia following acute herpes zoster (1 study, 40 participants). No studies examined acute postoperative pain. Fourteen studies investigated chronic neuropathic pain: two lasted eight weeks, others were four weeks or less (mean 3 weeks, median 2 weeks). Five had low reporting quality. Ten involved fewer than 50 participants; mean and median maximum treatment group sizes were 34 and 29. Outcome reporting was inconsistent. Most placebo controlled studies indicated that carbamazepine was better than placebo. Five studies with 298 participants provided dichotomous results; 70% improved with carbamazepine and 12% with placebo. Carbamazepine at any dose, using any definition of improvement was significantly better than placebo (70% versus 12% improved; 5 studies, 298 participants); relative benefit 6.1 (3.9 to 9.7), NNT 1.7 (1.5 to 2.0). Four studies (188 participants) reporting outcomes equivalent to 50% pain reduction or more over baseline had a similar NNT. With carbamazepine, 66% of participants experienced at least one adverse event, and 27% with placebo; relative risk 2.4 (1.9 to 3.1), NNH 2.6 (2.1 to 3.5). Adverse event withdrawals occurred in12 of 323 participants (4%) with carbamazepine and 0 of 310 with placebo. Serious adverse events were not reported consistently; rashes were associated with carbamazepine. Five deaths occurred in patients on carbamazepine, with no obvious drug association. Authors’ conclusions Carbamazepine is effective in chronic neuropathic pain, with caveats. No trial was longer than four weeks, of good reporting quality, using outcomes equivalent to at least moderate clinical benefit. In these circumstances, caution is needed in interpretation, and meaningful comparison with other interventions is not possible.

A Retrospective Study: The Off-Label Use of Anticonvulsants at a Private Hospital in Indonesia

“…Research on the use of carbamazepine in other than trigeminal neuralgia has lacked evidence. Regarding central poststroke pain, there is only one study, while on DPN there is some research but also a low evidence level, similarly for PHN [24,25]. Carbamazepine in Indonesia has a distribution license for the prophylaxis of indications of manic-depressive disorder that is not responsive to lithium, all types of epilepsy, except petit mal, and trigeminal neuralgia.…”

Geniculate neuralgia: a systematic review

“…There were two level 1 systematic reviews, which discussed the medical therapy of neuralgia. [20][21][22][23][24][25][26][27] In total, there have been fewer than 150 cases of geniculate neuralgia reported to date.…”

“…20 Overall, about 70 per cent of patients achieve some relief of chronic neuropathic pain. 21 Carbamazepine stabilises the inactivate state of synaptic voltage-gated sodium channels, thus making fewer channels available for subsequent opening. This blocks synaptic transmission and reduces the activation of afferent pain fibres.…”

Diabetic Neuropathies: Diagnosis and Management

“…Using the Cochrane criteria carbamazepine seems to be effective; on the other hand, no trial was longer than 4 weeks, of good reporting quality and used outcomes equivalent to at least moderate clinical benefit. In these circumstances, caution is needed in interpretation, and meaningful comparison with other interventions is not possible [72]. The efficacy of topiramate is also neutral in this condition [73,74].…”