Gabapentin Interactions, Side Effects, and Uses

Written by Dr. Diana Rangaves, PharmD, RPh

NowRx Contributor 

gabapentin prescription

What is Gabapentin?

Gabapentin is an anticonvulsant, also referred to as an antiepileptic drug. This class of medications is used to treat or manage epileptic seizures. The drug works by affecting the brain’s electrical activity and altering the activity of neurotransmitters and chemicals.

More specifically, these medications work to elicit a certain effect on the nervous system in two ways:

  • By blocking calcium or sodium excitatory channels, thus boosting the inhibitory activity of GABA (gamma-aminobutyric acid)
  • By blocking glutamate receptors

The drug is approved for use to either control or prevent partial seizures. It can be used with adults and is also safe for children aged 3 and older suffering from partial seizures.

Gabapentin Side Effects

Gabapentin side effects range from mild or moderate to severe. The common side effects of the anticonvulsant include:

  • Nausea and vomiting
  • Dizziness
  • Fatigue
  • Fever
  • Headache
  • Weight gain
  • Recurring infections
  • Double vision or unusual eye movements
  • Difficulty in speech
  • Memory loss

Monitoring the pattern of side effects is critical for advanced treatment. However, you should always consult with your doctor if any side effects become an issue.

Although most of the side effects above are mild or moderate, there are some serious side effects that require immediate attention.

For example:

  • Allergic reaction – Any allergic reaction should be addressed immediately. Some signs of an allergic reaction include a rash, blistering, hives, swelling, and itching. 
  • Change in mood and behavior – Anticonvulsants affect the normal activity of neurotransmitters and chemicals in the brain and nervous system. As a result, having mood or behavior changes is not unusual. However, you should consult with your doctor if these side effects progress.
  • Signs of liver problems – These may include liver abnormalities such as yellowing of the skin or whitening of the eyes, vomiting, unusual bruising, and bleeding. 

Does Gabapentin Cause Weight Gain?

Gabapentin may cause weight gain however it is not common.

Research shows that a handful of gabapentin users will suffer weight gain, usually around 5 to 6 weeks after use. In epileptic persons, weight gain may affect 3% of users above 12 years of age. This effect may also occur in pediatric epileptic patients between 3 to 12 years of using the drug.

Some of the weight gains are the result of increased appetite as taking gabapentin may increase your appetite. In other cases, fluid retention may be the result of a rare side effect caused by the anticonvulsant.

However, it is important to remember that weight gain is not common and you should always consult with your doctor before you decide to stop taking any medication.

Gabapentin Side Effects in Elderly

Gabapentin’s side effects in elderly persons can sometimes be more pronounced.

These side effects due to long-term use of the anticonvulsant can include:

  • Dizziness
  • Renal dysfunction
  • Drowsiness
  • Altered mental status

It is important to remember that the nervous system and brain of the elderly are different compared to that of the youth or younger adults. This means that even mild changes in the functioning of chemicals and neurotransmitters may have an adverse effect.

If you or a loved one is worried about any of the side effects they are experiencing while taking gabapentin be sure to connect with your doctor and discuss the options.

Does Gabapentin Make You Sleepy?

Gabapentin can make you sleepy as drowsiness and fatigue are two common side effects of the drug.

In fact, gabapentin is sometimes prescribed to people with insomnia to help promote sleep as some studies have shown it to be an effective tool to help with primary insomnia. However, it has not been approved for use as a sleep assistant.

Gabapentin has been shown to help people with sleeping problems in several ways, including:

  • Improve total sleep time
  • Decreasing spontaneous arousal (waking up)

This can be crucial for helping individuals with medical conditions such as bipolar disorder or alcohol dependence where sleeping is already an uphill task.

Gabapentin Interactions

Gabapentin as a prescription drug is fit for combination with around 21 drugs as their interaction is mild. However, the use of gabapentin with other medications that cause drowsiness or slow down breathing can be very dangerous.

It is important to always consult with your doctor and pharmacists about the medications you are taking before starting any new regimen.

If you have questions about a specific medication other than those listed below, be sure to talk with you doctor or pharmacist. You can also call one of our NowRx locations and a licensed pharmacist will be happy to assist you.

Can I Take Ibuprofen With Gabapentin?

Yes, you can use Ibuprofen with Gabapentin. Ibuprofen is a mild to moderate strength nonprescription painkiller which has no known effect on interaction with gabapentin. However, some strong painkillers may contain opiates, e.g., morphine which enhances the absorption of the antiepileptic drug. As a result, this can increase the side effects of Gabapentin or intensify them.

Gabapentin and Alcohol

Like many other medications, mixing gabapentin with alcohol is greatly discouraged. Alcohol has the same effect as opiates in strong pain killers, which can increase the side effects of the anticonvulsant. Some of the side effects that may be heightened when mixing gabapentin with alcohol include.

  • Loss of coordination 
  • Dizziness
  • Anxiety
  • Fatigue
  • Nausea
  • Drowsiness
  • Digestion issues
  • Headaches
  • Vomiting
  • Confusion

Alcohol is also known to take a toll on patients suffering from partial seizures or neurogenic issues. For this reason, mixing alcohol and gabapentin is detrimental.

Is Gabapentin a Controlled Substance?

Gabapentin is not currently classified as a controlled substance. However, some states have passed laws that monitor the medication’s use.

A controlled substance is a drug that is watched by the government because of the potential for abuse or addiction. The controlled aspect refers to the way the substance is made, prescribed, and distributed. Controlled medications may be legal or illegal depending on their accepted medical use.

All legal controlled substances require a prescription from a licensed medical professional and require identification when being dispensed at the pharmacy.

Questions About Gabapentin

Did we answer all your questions about gabapentin?

If so, consider subscribing to our newsletter where we send out health tips, medication information, and pharmacy resources completely free.

Otherwise, if you have a specific question about gabapentin that we didn’t cover, please don’t hesitate to reach out to us at


Domecq JP, Prutsky G, Leppin A, et al. Drugs Commonly Associated With Weight Change: A Systematic Review and Meta-analysis. J Clin Endocrinol Metab. 2015 Feb; 100(2):363–370.

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Eating & Physical Activity to Lose or Maintain Weight. January 2019. Available at: [Accessed September 14, 2020].

Gabapentin For Sleep & Insomnia: Does It Help? – Mental Health Daily

Disclaimer: This website does not provide medical advice and the information provided throughout the website, including but not limited to, text, graphics, images, and other material are for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment and you should always seek the advice of your physician or other qualified health care providers if you have questions regarding a medical condition or treatment or before starting or stopping any healthcare or health related regimen. Do not ever disregard or delay seeking medical advice from a qualified professional because of something you have read on