With the help of other medications, Gabapentin is used to prevent and treat seizures. This drug has also been proven effective in treating neuropathic pain from shingles in adults. However, some people have also been taking Gabapentin for its non-official uses such as migraines and insomnia.

It works through the increase of production of GABA, a neurotransmitter acting as nerve-calming agent. At the same time, it inhibits the release of glutamate, a neurotransmitter which “excites” other nerve cells. This is believed to be the reason behind epileptic seizures as well as transmitting pain signals the brain.

Gabapentin And Weight Gain

In a research conducted by DeToledo et al., twenty-eight patients who had seizure disorder received high dosages of Gabapentin amounting to greater than three thousand milligrams a day continuously for at least 12 months.

The end of the experiment showed no evidence to support that Gabapentin caused weight gain. Only ten patients gained more than 10 percent of their original weight, 15 patients gained five to ten percent of their baseline weight, while the rest did not display such changes. (1)

Until today, there is no research proving the drug Gabapentin cause weight gain. In fact, the same experiment shows that three of the people experimented on even lost weight.

This may seem to be only the case for a slim minority, but weight increase was very prominent for the majority only during the second to third months of the treatment. In the onset eighth and ninth months, most patients stabilized.

Why Do A Lot Of People Report Weight Gain With Gabapentin?

What those people experience is only a result of the side effects of Gabapentin and not of Gabapentin itself. Here are the most common ways how Gabapentin’s side effects can cause weight gain. (2)

  • Drowsiness: Responding to drowsiness through sleep reduces your overall physical activity, thus resulting in weight gain. Failure to reduce your food intake while having fewer activities inevitably leads to increased weight.
  • Fatigue: A common side effect of Gabapentin, fatigue can result to engaging in less physical activities.
  • Slower Metabolism: Along with the decrease in glutamate, an increase in GABA reduces physiological arousal which in turn leads to weight gain.

Factors Leading To Weight Gain With Gabapentin(3)

  • Physical Activities: It is important to note your physical activities before and during the treatment. Changes between the two may be the culprit behind your increased weight.
  • Eating Habits: Although depending entirely on your genetics, diet is usually correlated with weight gain.
  • Time Span: Look into body changes on both the short-term and long-term. As in the experiment, patients increased weight only in the second and third months while it stabilized during the eighth and ninth months.
  • Genetics: This dictates how your body will react to the drug, and what side effects you will

How Can I Prevent Weight Gain With Gabapentin?

Gaining weight while taking Gabapentin is not something to worry about. Unless you have become excessively overweight or morbidly obese, then you can rest assured that this is just something normal when using the drug.

Nevertheless, it is understandable that some people are very conscious when it comes to their figure. It may be because of an underlying health problem, or simply because it makes them more comfortable.

Hence, here are some ways you can control your weight while taking Gabapentin:

  • Exercise: not does it only lower your body fat, exercising is a great way to improve other aspects regarding your health. Exercising has been proven to improve both the performance of a person’s heart and his mental and psychological health.
  • Eat healthier: the emphasis is on the word “healthier.” Eating less has been proven to be an ineffective way to lose weight. Not only that, by eating less, you may worsen your health compared to how it was even before Gabapentin. (4)

Gabapentin may gain you a few extra inches, but the benefit that it can give you far outweighs it. Just remember to exercise more and eat healthier.


Changes in body weight with chronic, high-dose gabapentin therapy by DeToledo et al. (1997). Retrieved August 8, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/9263379

Diet Myth News Flash: Eating Less Does Not Cause Fat Loss. (n.d.). Retrieved August 8, 2017, from Ben Greenfield Fitness: https://bengreenfieldfitness.com/2013/12/diet-myth-news-flash-eating-less-cause-fat-loss/

Neurontin. (n.d.). Retrieved August 8, 2017, from Drugs: https://www.drugs.com/neurontin.html