What Are The Side Effects Of Gabapentin In The Elderly?

The elderly are an especially vulnerable population when it comes to medications. 

As we age, our bodies naturally begin to slow down. 

As a result, our bodies become less able to process drugs as quickly or efficiently as they used to. 

This means that the medicines we take have a higher chance of having side effects.

Gabapentin is a medication that has been shown to help with the symptoms of various conditions. 

It is an anticonvulsant and is sometimes prescribed to treat aggressivity symptoms in the elderly with dementia. 

However, some people who take gabapentin for these purposes experience side effects such as dizziness, sleepiness, and sedation. Is there anything else we need to know?

In this article, we will look at the different gabapentin side effects in the elderly and see if they differ from those found in younger patients.

What is gabapentin?

Gabapentin is an anti-seizure drug used to treat some types of epilepsy and neuropathic pain when no other pain medications are effective. In recent years, it has become a popular alternative for those who have fibromyalgia. 

Although it has been used for a long time, compared to opioids, there have only been a few studies that have looked at its side effects in the elderly population.

The drug works by increasing the brain concentration of the neurotransmitter gamma-aminobutyric acid (GABA). This neurotransmitter is an inhibitor substance that reduces cell signaling and calms nerve cells down. Thus, it is typically used to relieve pain caused by overactive nerve terminals that keep sending pain signals, causing ear, eye, and jaw pain, back pain due to sciatica, and more.

Brand names of gabapentin are Neurontin, Gralise, and Horizant. Gabapentin is available in tablets, capsules, extended-release tablets, and oral solutions. Gabapentin injections are not available in the market.

What are the side effects of gabapentin in the elderly?

All drugs have side effects. Even if you decide not to take them, you can face undesired consequences. Thus, every decision we make can have pros and cons, and all we have to do is weigh the benefits against the risks.

The elderly are more likely to experience the side effects of gabapentin, which include:

Feeling sleepy, tired, or dizzy

This is perhaps the most common side effect, and it happens because gabapentin inhibits neuronal transmission.

Nausea and vomiting

It depends on the patient and the dose. Gabapentin can induce nausea and vomiting, but it can also be used to prevent these symptoms in patients under chemotherapy

Swollen arms and legs

More than 7% of patients under gabapentin can experience swelling due to liquid retention in their arms and legs. This is much more common in older adults with blood circulation problems.

Blurred vision

Similarly, gabapentin can sometimes trigger edema (liquid retention) in the eyes, which causes blurred vision. Other side effects are visual field constriction and double vision.

Difficulty getting an erection

Erections need a vascular and nervous component to take place. If you’re inhibiting nerve conduction with gabapentin, it is no surprise that you will take longer to achieve an erection. Seniors with a baseline erectile dysfunction problem can worsen their symptoms. 

Weight gain

Gabapentin could make you gain weight because it can increase appetite and hunger. But how does gabapentin affect appetite? A recent study reveals that it might be related to a slight change in the gut-brain axis.

Memory problems

They are related to a “lazy” brain because you’re basically reducing nerve transmission. Thus, it is a temporary problem that goes away as the medication is cleared from your blood.

Headaches

If you’re on gabapentin, there’s also a chance that you experience headaches as a side effect. 

Trembling or shaking

Gabapentin may sometimes induce tremors, tics, and involuntary muscle movement as a side effect. Gabapentin may also induce myoclonus, described as jerking movements or muscle twitching.

Heart rhythm abnormalities

This side effect of gabapentin is more common in older adults and can be described as heart palpitations. In some cases, it can be a mild symptom. 

Still, gabapentin’s cardiac side effects sometimes include a severe alteration of the heart rhythm called atrial fibrillation and other types of arrhythmia.

Gabapentin can also have long-term side effects when administered for an extended period. Neurontin side effects in the long long-term include:

• The mental health side effects described below are more common with long-term treatment
• Behavioral changes
• Weakened muscles

Many older adults, their families, and caregivers usually have many questions about this drug. Here’s the answer to some frequently answered questions about gabapentin side effects in the elderly:

Does gabapentin affect urination or cause incontinence?

Incontinence is a rare side effect of gabapentin, and it has been described in some older adults. Gabapentin may trigger frequent urination because it relaxes the external urethral sphincter and promotes detrusor hyperactivity. This is the muscle that holds the urine in your bladder. 

Gabapentin urinary side effects are not common in most patients, but the odds can be against you if you have a baseline urinary problem.

Can gabapentin cause dehydration?

Some patients report a sensation of a dry mouth after taking gabapentin. But moderate and severe dehydration is a rare side effect in patients taking gabapentin. 

There is no formal study about dehydration in these patients. But it is apparently more common in females after 60 years when they take the drug for less than one month. Still, the prevalence of this side effect is around 1%.

Does gabapentin cause flatulence, gastritis, and stomach ulcers?

Some patients experience flatulence and increased gas production after taking this drug. They may also have diarrhea or constipation. 

However, gabapentin does not cause erosion in the stomach and shouldn’t trigger upper stomach pain. 

What’s more, gabapentin has been posed as an adjunctive drug to reduce the severity of gastrointestinal symptoms in patients with dyspepsia or indigestion. Still, it is worth noting that every patient is different and can experience different side effects.

Can gabapentin cause itching, numbness, and tingling as a side effect?

Yes, people under gabapentin can sometimes experience numbness, tingling, or itching. This is known as dysaesthesia. 

But how does gabapentin cause numbness and other forms of dysaesthesia? 

It is associated with altered nervous transmission. It is similar to what you feel after receiving anesthesia in a part of your body. The sensation changes as anesthesia start to take place.

Can gabapentin increase anxiety or have other mental side effects?

Gabapentin usually has the opposite effect. It favors GABA signaling, which is an inhibitory neurotransmitter. Thus, patients typically feel less anxious and may even feel sedated, improving their sleep quality. 

However, some people’s nervous systems respond differently. Suppose you feel gabapentin is making anxiety or restlessness worse or making depression or aggressivity worse as a side effect. In that case, it is recommended to stop taking it and talk to your healthcare provider.

Are the side effects of gabapentin different in the elderly compared to younger patients?

The adverse reactions to gabapentin in the elderly can be worse or more frequent in older adults. 

They usually have more health conditions and have multiple prescriptions to control chronic diseases. They may have chronic pain that requires opioid drugs or need tranquilizers to sleep at night.

Such polypharmacy, or using many drugs to control various conditions, should be noted in the elderly before prescribing gabapentin. Then, patients and their caregivers should be extra alert and detect the symptoms mentioned above to inform the doctor. Gabapentin could be replaced, or an appropriate elderly dose can be reached after a few adjustments.

Some side effects mentioned above are rare, and the only cases recorded in literature are in older adults. For instance, dehydration and incontinence are rarely or never found in younger patients. They are also not common in older adults, but there’s a slight chance with some cases recorded in clinical trials.

How to reduce the side effects of Gabapentin

Gabapentin pills can have very uncomfortable side effects. Here are a few recommendations and precautions you can take to reduce the chance of a drug reaction:

• Follow the instructions by your doctor and do not increase or reduce the dosage or form of administration by yourself.
• You can take your dose with an evening meal or in a fasted state. Make sure you’re always doing the same when you take your dose.
• Starting your gabapentin treatment and quitting the drug should be done progressively. Ask your doctor for guidance on how to do it, which usually involves using a half-tablet and spacing your doses effectively.
• Space the doses evenly throughout the day. Inform your doctor if you experience side effects at work, especially if you work with heavy machinery or dangerous implements.

What are the dangers of taking Gabapentin?

There are some gabapentin warnings you should know before using this drug.

If you or an elderly under your care take gabapentin and experiences fever, hives, a skin rash, swelling in the face or mouth, breathing problems, and swollen lymph nodes, it is important to stop using the drug and call your doctor immediately as it could be due to a hypersensitivity problem.

Other gabapentin major side effects include hallucinations, weakness or muscle pain in patients under dialysis treatment, and long-lasting stomach pain.

After hospitalization, some patients may need to change their gabapentin dose or stop gabapentin before surgery, but that’s up to your doctor. 

In some cases, gabapentin can be used before surgery to reduce postoperative pain and the need for opioid-prescribing drugs. However, the dangers of gabapentin should be evaluated depending on what other medications you’re using.

What to avoid while taking gabapentin

The main contraindication of gabapentin is for patients with myasthenia gravis or myoclonus. It may also be contraindicated if you suffer from severe depression, COPD, or chronic kidney disease.

Gabapentin should not be taken in combination with narcotic pain medicines, anxiety, or sleeping pills without consulting your doctor first. Be careful around alcohol, and talk to your doctor to decide whether to drink or not and how much is appropriate for you.

For a complete list of foods to avoid while taking gabapentin, we have prepared a dedicated article on the topic.

Conclusion

Gabapentin is commonly used for neuropathic pain relief in all stages of life. But how safe is gabapentin for older adults? What are the main gabapentin side effects in the elderly?

Older adults have a higher prevalence of side effects due to overlapping health conditions and polypharmacy. However, in most cases, they can use gabapentin safely and only need to adjust their dose and follow their doctor’s instructions.

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