Gabapentin is well-tolerated by most patients with few side effects. As with most medications, the higher the dose you take, the more likely you are to experience adverse side effects. Gabapentin is no exception to this rule.
Classed as an anticonvulsant, Gabapentin is approved by the FDA for the treatment of nerve pain and seizures. It’s also used off-label for treating restless leg syndrome, anxiety, and insomnia. When used off-label, it’s typically at a much lower dose than what’s used to treat epilepsy or neuropathy.
At Kick, we typically prescribe gabapentin in doses of 100-300 mg/day for treating insomnia. For comparison, the ”standard” dose of gabapentin for neuropathy is 1800-3600 mg/day.
The most common side effects of gabapentin
Side effects reports come from multiple sources. Because of this, they usually represent the average or standard dose of a drug, or in this case, 1800-3600 mg/day.
The most common side effects experienced after taking a standard dose of gabapentin are:
- Dizziness
- Drowsiness
- Lack of coordination
- Headache
- Nausea
- Water retention
- Weight gain
- Blurred vision
As we mentioned earlier, we typically prescribe a dose no higher than 300 mg/day at Kick. Because of this, you are less likely to experience these side effects than if you were taking a standard dose of gabapentin.
Serious gabapentin side effects
Severe side effects from gabapentin are extremely rare, but they can happen.
Very rare but serious side effects may include:
- Allergic reaction including skin rash, hives, and fever
- Worsening of seizures in those with a history of absence or myoclonic seizures
- Breathing problems for those with respiratory risk factors (e.g., asthma, COPD)
- Changes in mood or behavior, especially in children
- Depression that is worse or new
- Anxiety that is worse or new
- Suicidal thoughts
If you experience any of these symptoms, contact your healthcare provider immediately. You may need an alternative treatment plan or a lower dose.
Reducing your risk of adverse side effects from gabapentin
There’s no way to completely eliminate the risk of side effects from a medication. However, there are known risk factors for developing side effects when taking gabapentin. Strategies to reduce your risk include:
- Be clear with your doctor about any medication you are currently taking, as well as your medical history.
- Do not take new medication with gabapentin without consulting your doctor first. This includes over the counter medication.
- Do not change your dose or stop taking gabapentin suddenly without talking to your doctor.
- Never take more than the prescribed amount of gabapentin.
- Avoid alcohol while taking gabapentin.
Cross-medication interactions should be carefully evaluated by your doctor and pharmacist. Gabapentin interacts with a number of drugs, including those found over the counter.
Unless your healthcare provider decides it’s medically appropriate for you, avoid:
- Antihistamine-containing cold, cough and allergy products.
- Certain medicines for anxiety or sleep, such as Ambien.
- Certain medicines for depression, such as amitriptyline, fluoxetine, and sertraline.
- Certain medicines for seizures, such as phenobarbital and primidone.
- Certain medicines for stomach problems. Wait two hours after taking aluminum and magnesium-containing antacids before taking gabapentin.
- General anesthetics, local anesthetics, or muscle relaxants given before surgery.
- Narcotic pain medicines.
Frequently asked questions about gabapentin side effects
What is the biggest side effect of gabapentin?
11-28% of patients experience dizziness as a side effect from gabapentin.
This usually presents as a mild side effect and most people are able to continue their daily life. If you experience dizziness and it worries you or interferes with your daily activities, talk to your doctor immediately.
Does gabapentin cause confusion in the elderly?
Gabapentin causes confusion in fewer than 1% of elderly patients.
However, children and the elderly are more likely to experience side effects from gabapentin generally, so if you notice new symptoms of confusion in yourself or a loved one, speak to your doctor as soon as possible.
Can gabapentin lead to dementia?
Currently, there’s no data to suggest that gabapentin causes dementia. That said, while it’s sometimes used to treat behavioral or sleep problems in those with dementia, it should be evaluated carefully for cross-medication interaction in elderly patients.
Does gabapentin cause weight gain in women?
Although affecting just 2-3% of patients, gabapentin can cause weight gain in both men and women.
Typically, the weight gain is a result of the side effects – increased appetite or reduced activity – rather than a side effect itself.
Can gabapentin affect your bowel movements?
Gabapentin has a slight chance of causing constipation (1-4% of patients) or diarrhea in some patients.
Symptoms are usually short lived and cease upon discontinuation of medication.
What are the long-term effects of taking gabapentin?
When taking gabapentin long term, side effects are typically related to withdrawal symptoms with abrupt discontinuation. Gabapentin withdrawal symptoms can include:
- Mood changes
- Behavioral changes
- Depression
- Anxiety
- Weakened muscles
When being used as a treatment for insomnia, gabapentin should be used as a supplement, not a long term plan. Insomnia treatments at Kick include cognitive behavioral therapy to help you fix your sleep for good.
Can gabapentin cause erectile problems?
Immediate-release gabapentin has a slight chance of causing impotence, occurring in 2% of patients.
If you experience any symptoms that do not go away or concern you, speak with your healthcare provider. You may be able to lower your dose to reduce the risk of side effects.
How do I stop gaining weight on gabapentin?
Most gabapentin-related weight gain happens from either increased appetite or decreased activity. Because of this, an effective way to combat weight gain while taking gabapentin is to make conscious decisions around your dietary intake or activity level.
If you continue to experience problems with weight gain, speak to your doctor for advice specific to your circumstances.
What is the average weight gain on gabapentin?
If you gain weight while taking gabapentin, it will probably be 5-10% of your initial weight over a span of 12 months.
Lifestyle factors and dose can play a significant role in determining how much, if any, weight you gain.
One study looked at the results of patients taking a high dose (3,000 mg) of gabapentin for 12+ months. They found that:
- ~23% of patients gained >10% of their initial weight.
- ~34% gained 5 - 10% of their initial weight
- ~36% experienced zero weight gain
- ~7% actually lost 5-10% of their initial weight
Can gabapentin make you lose weight?
Yes, some patients experience mild weight loss while taking gabapentin. It isn’t fully understood why, but in rare cases, gabapentin can cause digestive problems and nausea, potentially leading to weight loss.
However, weight gain or no change in weight are much more likely side effects.
How long can you stay on gabapentin for?
That depends on why you’ve been prescribed gabapentin.
If you have epilepsy, it’s very likely you’ll be taking gabapentin for many years, even once your condition is under control.
Those using gabapentin for nerve pain will also probably take it for several months (or longer) to keep it from coming back. However, when using gabapentin to treat insomnia, most patients can expect a duration of several months. As always this will vary depending on your circumstances.
When used as part of a treatment plan for anxiety, gabapentin is typically prescribed on an as-needed basis.
Does gabapentin reduce blood pressure?
Some animal studies have shown gabapentin reduces blood pressure, but more studies are needed to replicate these results in humans.
Does gabapentin increase blood pressure?
Yes, under certain circumstances gabapentin has the potential to increase blood pressure in some patients. The mechanism for how gabapentin affects blood pressure isn't fully understood, but it’s thought that it affects myogenic (muscle) tone and increases water retention, leading to higher blood pressure.
Can gabapentin keep you awake?
Gabapentin is highly unlikely to keep you awake at night. One of its most prominent side effects is drowsiness, which is why we prescribe it at low doses as part of our sleep treatments at Kick.
Gabapentin enhances slow-wave sleep in patients with primary insomnia. It also improves sleep quality by elevatoring sleep efficiency and decreasing spontaneous arousal.
How long before bed should I take gabapentin for sleep?
You should take gabapentin immediately before going to bed when using it to improve sleep quality.
Never use this medication if you won’t be able to go to bed right away and stay asleep for at least 7 hours.