Anticonvulsant drugs for management of pain: a systematic review.
OBJECTIVE
To determine effectiveness and adverse effects of anticonvulsant drugs in management of pain.


METHODS
Systematic review of randomised controlled trials of anticonvulsants for acute, chronic, or cancer pain identified by using Medline, by hand searching, by searching reference lists, and by contacting investigators.


METHODS
Between 1966 and February 1994, 37 reports were found; 20 reports, of four anticonvulsants, were eligible.


METHODS
Numbers needed to treat were calculated for effectiveness, adverse effects, and drug related withdrawal from study.


RESULTS
The only placebo controlled study in acute pain found no analgesic effect of sodium valproate. For treating trigeminal neuralgia, carbamazepine had a combined number needed to treat of 2.6 for effectiveness, 3.4 for adverse effects, and 24 for severe effects (withdrawal from study). For treating diabetic neuropathy, anticonvulsants had a combined number needed to treat of 2.5 for effectiveness, 3.1 for adverse effects, and 20 for severe effects. For migraine prophylaxis, anticonvulsants had a combined number needed to treat of 1.6 for effectiveness, 2.4 for adverse effects, and 39 for severe effects. Phenytoin had no effect on the irritable bowel syndrome, and carbamazepine had little effect on pain after stroke. Clonazepam was effective in one study for temporomandibular joint dysfunction. No study compared one anticonvulsant with another.


CONCLUSIONS
Anticonvulsants were effective for trigeminal neuralgia and diabetic neuropathy and for migraine prophylaxis. Minor adverse effects occurred as often as benefit.
McQuay
H
H
Oxford Pain Relief Unit, Churchill Hospital.
Carroll
D
D
Jadad
A R
AR
Wiffen
P
P
Moore
A
A
D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use*; D002220:Carbamazepine / Q000009:adverse effects / Q000627:therapeutic use; D002998:Clonazepam / Q000009:adverse effects / Q000627:therapeutic use; D003929:Diabetic Neuropathies / Q000188:drug therapy; D006801:Humans; D010146:Pain / Q000188:drug therapy*; D010672:Phenytoin / Q000009:adverse effects / Q000627:therapeutic use; D016896:Treatment Outcome; D014277:Trigeminal Neuralgia / Q000188:drug therapy; D014635:Valproic Acid / Q000009:adverse effects / Q000627:therapeutic use
D000927:Anticonvulsants; D002220:Carbamazepine; D002998:Clonazepam; D014635:Valproic Acid; D010672:Phenytoin