Pregabalin Vs Gabapentin- A Comprehensive Comparison of Two Popular Neuropathic Pain Medications

Neuropathic pain is a complex and often debilitating condition that affects millions of people worldwide. For those struggling to manage this type of pain, medications like Pregabalin and Gabapentin are frequently prescribed to provide relief. Although both drugs belong to the same class of medications, known as gabapentinoids, they differ in several key aspects, including their mechanism of action, effectiveness, and side effect profiles.

In this blog, we will take an in-depth look at Pregabalin and Gabapentin, comparing their uses, benefits, and potential side effects. This guide will provide you with the information needed to make an informed decision in consultation with your healthcare provider.

Introduction To Pregabalin And Gabapentin

Pregabalin and gabapentin are anticonvulsant medications primarily used to treat nerve-related conditions. Both are structurally similar and have a similar mechanism of action.

Gabapentin is commonly prescribed for conditions like neuropathic pain, postherpetic neuralgia, and seizure disorders. It may also be used for restless leg syndrome and anxiety.

Pregabalin has similar uses but is typically preferred for conditions such as fibromyalgia, generalized anxiety disorder, and diabetic neuropathy, in addition to its role in treating seizures.

Similarities Between Pregabalin And Gabapentin

FDA Approval

Gabapentin and Pregabalin are both FDA-approved medications. The U.S. Food and Drug Administration approved multiple applications for Pregabalin or Lyrica on December 30, 2004. On the other hand, Gabapentin use was approved by the FDA in 1993 [1,2].

Mechanism Of Action

Both pregabalin and gabapentin work by binding to a calcium channel in the central nervous system. This binding reduces calcium influx into nerve cells, which in turn decreases the release of excitatory neurotransmitters. This helps reduce neuronal excitability and helps in neuropathic pain management and seizures.

Dosage And Administration

• Both medications are typically taken orally in the form of capsules or tablets.
• They are usually initiated at low doses to minimize side effects.
• Dosing schedules vary, but both can be taken multiple times a day depending on the severity of the patient’s condition.

Dependence And Withdrawal

Both drugs have a lower potential for abuse and dependence.

Abrupt discontinuation of either drug can lead to withdrawal symptoms, including anxiety, insomnia, nausea, and seizures (though this is more common with higher doses).

What Is The Difference Between Gabapentin And Pregabalin?

Despite their similarities, these medications have distinct characteristics, making it essential to understand their differences when considering treatment options.

Some of the differences between pregabalin and gabapentin are listed below.

Onset Of Action

Pregabalin tends to have a faster onset of action and may be more potent than gabapentin, so it is often used when a quicker therapeutic effect is needed [3].

Additional Medical Benefits

Pregabalin is approved for additional uses, such as generalized anxiety disorder and social anxiety disorder, which gabapentin is not typically used for.

Duration Of Action

Pregabalin has a longer duration of action, with its therapeutic effects lasting between 8 to 12 hours [4]. Meanwhile, Gabapentin’s action lasts for about 5 to 7 hours [5].

The table below shows how long each drug takes to reach its maximum concentration in your blood.

Drug Schedule

The Drug Enforcement Administration (DEA) has classified Pregabalin as a Schedule V controlled substance, indicating it has some potential for abuse and physical dependence [6]. In contrast, Gabapentin is not currently classified as a controlled substance, meaning it has a lower risk for misuse [7].

Comparison Of Their Clinical Uses And Benefits

Pregabalin and Gabapentin are two widely prescribed medications that are commonly used to manage conditions such as neuropathic pain, anxiety, and seizures.

Gabapentin Vs Pregabalin For Neuropathic Pain

Both gabapentin and pregabalin are first-line treatments for neuropathic pain.

Pregabalin has consistently demonstrated superior efficacy compared to gabapentin in managing neuropathic pain. A 2010 study by Howard N Bockbrader et al. comparing Gabapentin and Pregabalin found that both drugs reduce pain. However, gabapentin’s effect was better at 3600 mg/day, while pregabalin continues to improve pain relief up to 450 mg/day. This suggests pregabalin is more potent at lower doses, whereas Gabapentin, while effective, often requires higher doses to achieve similar levels of pain relief [8].

Pregabalin Vs Gabapentin For Anxiety

Pregabalin and gabapentin are sometimes used off-label to manage anxiety disorders, particularly generalized anxiety disorder (GAD). Both drugs work by altering the activity of neurotransmitters to reduce neural excitability and lower anxiety symptoms.

Pregabalin has shown efficacy in reducing anxiety symptoms, particularly in patients with GAD. A 2005 study by Karl Rickels et al. demonstrated its effectiveness in managing both short-term and long-term anxiety symptoms [9].

Gabapentin is also used for anxiety but is typically considered less potent than pregabalin. A 2017 study by Matej Markota and Robert J Morgan reported modest improvements in anxiety symptoms with gabapentin in individuals with social phobia [10].

Gabapentin Versus Pregabalin- Safety And Considerations

• Both Gabapentin and Pregabalin should not be taken by pregnant and breastfeeding mothers.
• It is not advisable to take these medications with alcohol.
• Both pregabalin and gabapentin can cause drowsiness, dizziness, and sedation. This may make it difficult to perform tasks that require full alertness, like driving.
• Combining Pregabalin and Gabapentin may increase the risk of respiratory depression, especially in people with respiratory conditions or when taken with alcohol.
• Avoid taking these medications without consulting a doctor if you suffer from a kidney or liver disorder.

Gabapentin Vs Pregabalin Side Effects

The side effects of both Gabapentin and Pregabalin are similar; however, some studies indicate that Pregabalin may have a lower risk of adverse effects. Two of the most common side effects of Gabapentin and Pregabalin include sleepiness and dizziness. Some of the other side effects of taking these two medications include-

Side effects of Gabapentin include-

• Drowsiness.
• Headache.
• Dry mouth.
• Increased appetite.
• Shaking.
• Blurred vision.
• Constipation.
• Back or joint pain.
• Ear pain.
• Runny nose.
• Flu-like symptoms.
• Red, itchy eyes.
• Rash.
• Weight gain.
• Shortness of breath.
• Itching.
• Swelling of the face, tongue, lips, or eyes.

Side effects of Pregabalin include-

• Headache.
• Chest pain.
• Gas and bloating.
• Increased appetite.
• Weight gain.
• Back pain.
• Dry mouth.
• Flu-like symptoms.
• Red, itchy eyes.
• Shortness of breath.
• Rash.
• Constipation.
• Blurred vision.

In rare cases, hair fall associated with Pregabalin intake has been reported. However, studies indicate that it is a temporary side effect and stops within 15 days of treatment discontinuation.

Pregabalin Vs Gabapentin Weight Gain

Pregabalin has been consistently associated with weight gain as a side effect. It may cause weight gain, particularly at higher doses and with prolonged use. In 14 week study, 9% of patients treated with Pregabalin gained weight. The drug is also associated with increased appetite and fluid retention, which can contribute to weight gain [11]. Peripheral edema (swelling in the hands, legs, and feet) is another possible side effect occurring in 6% of Pregabalin patients [11].

Gabapentin has also been associated with weight gain, though the risk is generally lower than with pregabalin. Studies show that 3% of individuals with epilepsy and 2% of those with postherpetic neuralgia experienced weight gain [12]. The weight gain is typically due to increased appetite, fluid retention (peripheral edema), or reduced exercise due to fatigue.

Weight gain from Gabapentin is generally mild (2.5 to 5 pounds) and is more common within the first three months of treatment [13].

Pregabalin Vs Gabapentin- Drug Interaction

The intake of Pregabalin and Gabapentin with other medications can cause drug interaction. Some of the medications that should not be taken with these anticonvulsants are listed below.

• alfentanil
• brexanolone
• butorphanol
• codeine
• dezocine
• esketamine
• fentanyl
• hydrocodone
• hydromorphone
• ketamine
• levorphanol
• methadone
• nalbuphine
• oxycodone

Apart from these medications, there are other possible drug interactions of Pregabalin and Gabapentin. Thus, it is recommended to consult a doctor before taking any medication with them.

Switching Between Gabapentin And Pregabalin

According to a study, when patients switched from gabapentin to pregabalin, they experienced better pain control. This was seen for both patients who had responded well to gabapentin and those who didn’t respond well to the medication. In fact, Pregabalin helped reduce pain more effectively than gabapentin [14].

A 2011 study by Masataka Ifuku et al. on replacing Gabapentin with Pregabalin found that Pregabalin is six times stronger than Gabapentin for relieving pain [15].

Dosage Conversion

While switching from Gabapentin to Pregabalin, the dosage adjustment can be done in the following way-

• Gabapentin ≤ 900 mg/day → Pregabalin 150 mg/day
• Taking Gabapentin dosage between 901 to 1500 mg/day → Pregabalin 225 mg/day
• Gabapentin dose between 1501 to 2100 mg/day → Pregabalin 300 mg/day
• Dosage of Gabapentin from 2101 to 2700 mg/day → Pregabalin 450 mg/day
• Taking a Gabapentin dose above 2700 mg/day → Pregabalin 600 mg/day

This conversion can be done either by starting pregabalin right after stopping Gabapentin or by gradually reducing the gabapentin dose while introducing pregabalin. Both methods were well-tolerated and worked effectively.

Is Pregabalin Better Than Gabapentin- Our Final Thoughts

Pregabalin and Gabapentin are both effective treatments for neuropathic pain and other conditions, but they differ in several key aspects. Pregabalin has faster absorption, onset of action, and greater potency, making it more effective for some patients.

While both medications share common side effects, such as dizziness and drowsiness, pregabalin is more likely to cause weight gain.

Ultimately, pregabalin may offer a more reliable and potent option, but the choice between the two should be based on individual patient needs and the specific condition being treated. Both medications can be safely transitioned from one to the other, and the decision should always involve careful consideration by a healthcare provider.