Gabapentin

Classification: B

Drug products: Anivo, Delarit, Gabapentin, Gabapentin 1A Farma, Gabapentin 2care4, Gabapentin Accord, Gabapentin Actavis, Gabapentin Aurobindo, Gabapentin Ebb, Gabapentin EQL, Gabapentin HEXAL, Gabapentin Medartuum, Gabapentin Nycomed, Gabapentin Orifarm, Gabapentin Orion, Gabapentin Pfizer, Gabapentin Ranbaxy, Gabapentin Rivopharm, Gabapentin Rosemont, Gabapentin Sandoz, Gabapentin Strides, Gabapentin Teva, Nelakap, Neurontin, Neurontin®

ATC code: N03AX12

Substances: gabapentin

Summary

Controlled studies on differences between men and women in efficacy of gabapentin regarding epileptic seizures or neuropathic pain are lacking but estimates from response in clinical studies do not indicate any significant differences. Reported information about pharmacokinetic differences between men and women is conflicting but are not considered to be of clinical relevance.

Additional information

Pharmacokinetics and dosing

Population data analyses indicate that the pharmacokinetic parameters for men and women are similar [1, 2]. One small clinical trial evaluated the effect of patient’s sex on the pharmacokinetics of gabapentin (18 men, 18 women). Following a single 400 mg oral dose gabapentin, Cmax was about 25% higher for women than for men, probably due to a smaller volume of distribution in women, as a result of their generally smaller size. However, the sex difference in Cmax values is not considered to be clinically important. The apparent elimination rate constant declined with increasing age for women but did not reach significance in relation with age for men. Since the relation between the apparent oral clearance and age was similar for men and women, the sex difference in relation between apparent elimination rate constant and age may be due to a sex-related difference in the relation between volume of distribution and age [3]. No sex differentiation in dosing has been recommended by the pharmaceutical company [4]. Individual dose-titration is recommended for all indications in both men and women.

Effects

No published studies with a clinically relevant sex analysis regarding the effects of gabapentin in epilepsy or neuropathic pain have been found. Estimates of response to gabapentin in epilepsy derived from clinical trials (398 men, 307 women) indicate no appearant sex differences [1].

Adverse effects

According to the pharmaceutical company, adverse effects were more common in men than in women [2], but studies with a clinically relevant sex analysis regarding adverse effects of gabapentin have not been published.

Reproductive health issues

Regarding teratogenic aspects, please consult Janusmed Drugs and Birth Defects (in Swedish, Janusmed fosterpåverkan).

Updated: 2020-08-28

Date of litterature search: 2019-08-28

References

Neurontin (gabapentin). DailyMed [www]. US National Library of Medicine. [updated 2019-07-01, cited 2019-08-28]. webplats
US Food and Drug Administration. Medical Review - Neurontin (gabapentin). Drugs@FDA [www]. [updated 2000-10-12, cited 2019-08-28]. länk
Boyd RA, Türck D, Abel RB, Sedman AJ, Bockbrader HN. Effects of age and gender on single-dose pharmacokinetics of gabapentin. Epilepsia. 1999;40:474-9. PubMed
Neurontin (gabapentin). Summary of Product Characteristics. Swedish Medical Products Agency [updated 2019-07-08, cited 2019-08-28].
Läkemedelsstatistik. Stockholm: Socialstyrelsen. 2019 [cited 2020-03-10.] länk

Authors: Linnéa Karlsson Lind

Reviewed by: Mia von Euler, Carl-Olav Stiller

Approved by: Karin Schenck-Gustafsson