Gabapentin versus nortriptyline in post-herpetic neuralgia patients: a randomized, double-blind clinical trial--the GONIP Trial.
BACKGROUND
Gabapentin and nortriptyline have not been compared in a randomized trial in post-herpetic neuralgia (PHN). The present study was, therefore, undertaken to determine their comparative efficacy and tolerability in the treatment of post-herpetic neuralgia.


METHODS
The study was a randomized, double-blind, parallel-group trial of 9 weeks duration. Adult PHN patients with history of > 8 weeks of PHN pain after healing of rash, a pain intensity of at least 40 mm on a 100 mm visual analog scale at screening and at randomization, and average pain score of at least 4 on the Likert scale during the baseline week were included in the study. Gabapentin and nortriptyline were given in incremental doses at 2-weekly intervals till a maximum tolerated dose was obtained. The primary efficacy parameter was change in pain score (11-point Likert scale) from baseline to the end of the study period.


RESULTS
70 patients were available for intention-to-treat analysis. The average pain scores on the Likert scale were significantly reduced at the end of study in both the treatment groups with 47.6% and 42.8% reduction in pain scores in nortriptyline and gabapentin groups, respectively. Patients showed significant improvement in sleep scores in both the treatment groups nortriptyline (46.0%) and gabapentin (52.0%). The VAS and the SF-MPQ scores for pain were significantly reduced in both the groups. Gabapentin was, however, better tolerated as compared to nortriptyline.


CONCLUSIONS
Gabapentin was shown to be equally efficacious but was better tolerated compared to nortriptyline and can be considered a suitable alternative for the treatment of PHN.
Chandra
K
K
Department of Pharmacology, PGIMER, Chandigarh, India.
Shafiq
N
N
Pandhi
P
P
Gupta
S
S
Malhotra
S
S
D000368:Aged; D000588:Amines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D002214:Capsules; D003509:Cyclohexanecarboxylic Acids / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D000077206:Gabapentin; D006801:Humans; D007024:Hypotension, Orthostatic / Q000139:chemically induced; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D009661:Nortriptyline / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D010147:Pain Measurement; D013997:Time Factors; D016896:Treatment Outcome; D016055:Urinary Retention / Q000139:chemically induced; D014987:Xerostomia / Q000139:chemically induced; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
D000588:Amines; D000700:Analgesics; D002214:Capsules; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin; D009661:Nortriptyline