The effect of gabapentin on neuropathic pain.
OBJECTIVE
To evaluate the effects of gabapentin on pain scores and opiate use.


METHODS
Retrospective review of patients charts who received gabapentin for at least 30 days. Data were collected concerning patients' diagnosis, current drug use, concurrent drug use, gabapentin dose, pain scores, and patient-reported side effects. Patients were divided into three groups based on their pain diagnosis; low back, neuropathic, and myofascial pain. The neuropathic group was subdivided into postherpetic neuralgia, diabetic neuropathy, sympathetically maintained pain, and phantom pain.


METHODS
Two tertiary referral teaching hospitals in southeastern Michigan.


RESULTS
A total of 122 charts were reviewed and included in this study. A significant decrease in pain scores with gabapentin was seen in the neuropathic pain group (paired t-test, p < .0001) but not in the low back pain group. Of the neuropathic pain group, patients with postherpetic neuralgia had the greatest decrease in pain scores. Ten patients showed a > 75% decrease in pain scores, of these: nine had a direct nerve injury, and one had postherpetic neuralgia. Opiate use was unchanged in all groups. Patients who were taking opiates had significantly less benefit with gabapentin use in terms of pain score. Patient-reported side effects were similar to those reported in a nonchronic pain population.


CONCLUSIONS
Gabapentin may be a useful adjunct for treating neuropathic pain with a minimum of side effects. Particular advantage may be gained with the use of this drug for postherpetic neuralgia and direct peripheral nerve injuries.
Rosenberg
J M
JM
Department of Anesthesiology, University of Michigan Health System, Ann Arbor, USA.
Harrell
C
C
Ristic
H
H
Werner
R A
RA
de Rosayro
A M
AM
D000085:Acetates / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000588:Amines; D000700:Analgesics / Q000627:therapeutic use*; D002648:Child; D003509:Cyclohexanecarboxylic Acids; D000077206:Gabapentin; D006801:Humans; D017116:Low Back Pain / Q000188:drug therapy; D008875:Middle Aged; D009209:Myofascial Pain Syndromes / Q000188:drug therapy; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D010523:Peripheral Nervous System Diseases / Q000150:complications / Q000188:drug therapy*; D012189:Retrospective Studies; D005680:gamma-Aminobutyric Acid
D000085:Acetates; D000588:Amines; D000700:Analgesics; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin