Gabapentin (Neurontin) versus ...

• Gabapentin vs Pregabalin
• Gabapentin vs Amitriptyline
• Gabapentin vs Lamotrigine
• Gabapentin vs Carbamazepine
• Gabapentin vs Phenobarbital
• Gabapentin vs Topiramate

Based on "Essential Psychopharmacology"
written by Stephen M. Stahl, MD, PhD

Painful diabetic neuropathy
In the study comparing the efficacy of gabapentin with amitriptyline for diabetic peripheral neuropathy pain, moderate or greater pain relief was experienced in 52% of patients with gabapentin and 67% of patients with amitriptyline. Study concluded that gabapentin does not appear to offer considerable advantage over amitriptyline and is more expensive 4.

Earlier study has shown that gabapentin produces greater improvements than amitriptyline in pain and paresthesia associated with diabetic neuropathy 2.

Chronic pelvic pain
Gabapentin alone or in combination with amitriptyline is superior to amitriptyline alone in the treatment of female chronic pelvic pain 3.

Peripheral neuropathic pain
In the double blind randomized trial both gabapentin and amitriptyline were effective for the management of peripheral neuropathic pain. However, improvement in shooting pain and patient satisfaction were significantly higher with gabapentin treatment. Also gabapentin was more effective in paroxysmal shooting pain than in other pain qualities 6.

Safety & Side effects
Gabapentin is better tolerated than amitriptyline. Side effects occur more frequently with amitriptyline than with gabapentin 2, 3, 6.

Gabapentin has no important drug interactions while amitriptyline has several clinically significant drug interactions (e.g. MAOI, cisapride, thyroid agents).

Gabapentin is more costly than amitriptyline and requires frequent dosing regimen.

Partial epilepsy:
Unblinded randomised controlled trial has shown that lamotrigine is significantly better than gabapentin in the treatment of partial onset seizures 1.

Epilepsy:
Gabapentin and lamotrigine are similarly effective and well tolerated in patients with newly diagnosed epilepsy 5 and elderly patients with epilepsy 18.

Results of randomised, double-blind study comparing gabapentin versus lamotrigine in newly diagnosed epilepsy 5	Gabapentin	Lamotrigine
Regimen	1,200 - 3,600 mg/day for 24 weeks	100 - 300 mg/day for 24 weeks
Exit event, number of patients	19 of 148 patients	19 of 143 patients
Median time to exit	69 days	48 days
Number of patients remained seizure free during the final 12 weeks of treatment	80 of 106 patients (75.5%)	73 of 96 patients (76.0%)
Number of patients withdrew from treatment because of drug-related adverse events	14 of 106 patients (8.9%)	15 of 96 patients (9.9%)

Mood disorders:
Controlled comparative study evaluated the efficacy of lamotrigine and gabapentin monotherapy versus placebo in refractory bipolar and unipolar mood disorders 12. Response rates were the following: lamotrigine 52%; gabapentin 26%; placebo 23%.

Pain relief:
Animal research has demonstrated that both lamotrigine and gabapentin have analgesic effect15. The analgesic effect of lamotrigine was more evident.

Epilepsy:

Unblinded randomised controlled trial has shown that carbamazepine is significantly better than gabapentin for patients with partial onset seizures 1.

Side effects and tolerability: Gabapentin is better tolerated and produces significantly fewer untoward cognitive effects compared with carbamazepine 8, 18.

The small randomized, open-label study13 compared gabapentin with phenobarbital for reducing symptoms of alcohol withdrawal. In the study the proportion of patients needing “rescue” phenobarbital for breakthrough signs and symptoms of withdrawal did not significantly differ between treatment groups (57% of the gabapentin group vs. 38% of the phenobarbital group). The proportion of those who failed to complete the trial also did not significantly differ between the groups.

The incidence of withdrawal symptoms, psychological distress, and serious adverse effects were similar. These findings suggest that gabapentin may be as effective as phenobarbital in the treatment of alcohol withdrawal.

Side effects: Gabapentin is better tolerated than topiramate16. Weight loss and numbness are common with topiramate. Dizziness, weight gain and somnolence are more common with gabapentin.

Unlike gabapentin, topiramate has an established risk of teratogenicity9.

Topiramate has prominent negative effects on cognition, whereas gabapentin has only minimal impact on cognitive abilities 6.

Migraine prophylaxis:
Both drugs are effective in migraine prophylaxis. Topiramate works slightly more efficaciously than gabapentin.

Results of comparative randomized open label control trial of topiramate and gabapentin in migraine prophylaxis16	Gabapentin	Topiramate
Reduction in average monthly migraine frequency	from 11.97 +/- 4.452 to 2.73 +/- 2.59	from 10.67 +/- 4.25 to 1.82 +/- 2.02
Reduction in severity	from 6.93 +/- 1.90 to 1.18 +/- 1.01	from 6.60 +/- 2.122 to 1.03 +/- 0.92
Reduction in the average duration of attacks	from 22.20 +/- 20.72 to 1.08 +/- 1.40 hours	from 25.77 +/- 22.32 hours to 1.05 +/- 1.06 hours
Adverse effects	dizziness, weight gain, somnolence	weight loss, numbness

• Gabapentin (Neurontin) Facts

• 1. Marson AG, Al-Kharusi AM, Alwaidh M, Appleton R, Baker GA, Chadwick DW, Cramp C, Cockerell OC, Cooper PN, Doughty J, Eaton B, Gamble C, Goulding PJ, Howell SJ, Hughes A, Jackson M, Jacoby A, Kellett M, Lawson GR, et al; SANAD Study group. The SANAD study of effectiveness of carbamazepine, gabapentin, lamotrigine, oxcarbazepine for treatment of partial epilepsy: an unblinded randomised controlled trial. Lancet. 2007 Mar 24;369(9566):1000-15. PubMed
• 2. Dallocchio C, Buffa C, Mazzarello P, Chiroli S. Gabapentin vs. amitriptyline in painful diabetic neuropathy: an open-label pilot study. J Pain Symptom Manage. 2000 Oct;20(4):280-5. PubMed
• 3. Sator-Katzenschlager SM, Scharbert G, Kress HG, Frickey N, Ellend A, Gleiss A, Kozek-Langenecker SA. Chronic pelvic pain treated with gabapentin and amitriptyline: a randomized controlled pilot study. Wien Klin Wochenschr. 2005 Nov;117(21-22):761-8. PubMed
• 4. Morello CM, Leckband SG, Stoner CP, Moorhouse DF, Sahagian GA. Randomized double-blind study comparing the efficacy of gabapentin with amitriptyline on diabetic peripheral neuropathy pain. Arch Intern Med. 1999 Sep 13;159(16):1931-7. PubMed
• 5. Brodie MJ, Chadwick DW, Anhut H, Otte A, Messmer SL, Maton S, Sauermann W, Murray G, Garofalo EA. Gabapentin versus lamotrigine monotherapy: a double-blind comparison in newly diagnosed epilepsy. Epilepsia. 2002 Sep;43(9):993-1000. PubMed
• 6. Keskinbora K, Pekel AF, Aydinli I. Comparison of efficacy of gabapentin and amitriptyline in the management of peripheral neuropathic pain. Agri. 2006 Apr;18(2):34-40. PubMed
• 7. Salinsky MC, Storzbach D, Spencer DC, Oken BS, Landry T, Dodrill CB Effects of topiramate and gabapentin on cognitive abilities in healthy volunteers. Neurology. 2005 Mar 8;64(5):792-8. PubMed
• 8. Meador KJ, Loring DW, Ray PG, Murro AM, King DW, Nichols ME, Deer EM, Goff WT. Differential cognitive effects of carbamazepine and gabapentin. Epilepsia. 1999 Sep;40(9):1279-85. PubMed
• 9. Holmes LB, Hernandez-Diaz S. Newer anticonvulsants: lamotrigine, topiramate and gabapentin. Birth Defects Res A Clin Mol Teratol. 2012 Aug;94(8):599-606. PubMed
• 12. Frye MA, Ketter TA, Kimbrell TA, Dunn RT, Speer AM, Osuch EA, Luckenbaugh DA, Cora-Ocatelli G, Leverich GS, Post RM. A placebo-controlled study of lamotrigine and gabapentin monotherapy in refractory mood disorders. J Clin Psychopharmacol. 2000 Dec;20(6):607-14. PubMed
• 13. Mariani JJ, Rosenthal RN, Tross S, Singh P, Anand OP. A randomized, open-label, controlled trial of gabapentin and phenobarbital in the treatment of alcohol withdrawal. Am J Addict. 2006 Jan-Feb;15(1):76-84.
• 14. Toth C. Substitution of gabapentin therapy with pregabalin therapy in neuropathic pain due to peripheral neuropathy. Pain Med. 2010 Mar;11(3):456-65
• 15. Szabo AZ, Bocsan IC, Suciu S, Buzoianu AD. Comparative animal study of the antinociceptive efficacy of lamotrigine and gabapentin for the management of pain. Acta Physiol Hung. 2015 Dec;102(4):363-71. PubMed
• 16. Zain S, Khan M, Alam R, Zafar I, Ahmed S. Comparison of efficacy and safety of topiramate with gabapentin in migraine prophylaxis: randomized open label control trial. J Pak Med Assoc. 2013 Jan;63(1):3-7.
• 18. Rowan AJ, Ramsay RE, Collins JF, et al. New onset geriatric epilepsy: a randomized study of gabapentin, lamotrigine, and carbamazepine. Neurology. 2005 Jun 14;64(11):1868-73. PubMed

Published: March 31, 2008
Last updated: May 20, 2017