From the Guidelines
No, pregabalin and gabapentin are not the same thing, though they are closely related medications that belong to the same class of drugs called gabapentinoids. Both medications work similarly by binding to calcium channels in the nervous system to reduce the release of excitatory neurotransmitters, which helps control seizures and nerve pain. However, pregabalin (brand name Lyrica) is more potent than gabapentin (brand names Neurontin, Gralise), requiring lower doses to achieve similar effects. Pregabalin also has better bioavailability (approximately 90% versus 33-66% for gabapentin) and a more predictable dose-response relationship 1. While both medications are used to treat neuropathic pain, fibromyalgia, and seizures, pregabalin has additional approved uses for anxiety disorders in some countries. Side effects for both medications are similar and can include dizziness, drowsiness, weight gain, and peripheral edema. Neither medication should be stopped abruptly as this can cause withdrawal symptoms; dosage should be gradually reduced under medical supervision.
Some key differences between pregabalin and gabapentin include:
- Bioavailability: Pregabalin has a higher bioavailability than gabapentin, which means that more of the medication is absorbed into the bloodstream 1.
- Dosage: Pregabalin typically requires lower doses than gabapentin to achieve similar effects 1.
- Pharmacokinetics: Pregabalin has linear pharmacokinetics, making it easier to dose and titrate, while gabapentin has nonlinear pharmacokinetics, requiring more careful titration 1.
- Approved uses: Pregabalin has additional approved uses for anxiety disorders in some countries, while gabapentin is primarily used for neuropathic pain, fibromyalgia, and seizures 1.
It's worth noting that both medications can be effective for treating neuropathic pain, and the choice between them often depends on individual patient factors, such as medical history, comorbidities, and personal preferences. Ultimately, the decision to use pregabalin or gabapentin should be made in consultation with a healthcare provider, taking into account the latest evidence and guidelines 1.
From the FDA Drug Label
Although the mechanism of action of pregabalin has not been fully elucidated, results with genetically modified mice and with compounds structurally related to pregabalin (such as gabapentin) suggest that binding to the alpha2-delta subunit may be involved in pregabalin's anti-nociceptive and antiseizure effects in animals
- Pregabalin and gabapentin are not the same thing, they are structurally related but have different properties and mechanisms of action.
- The fact that pregabalin is compared to gabapentin in the drug label suggests that they are related, but distinct medications. 2
From the Research
Comparison of Pregabalin and Gabapentin
- Pregabalin and gabapentin share a similar mechanism of action, inhibiting calcium influx and subsequent release of excitatory neurotransmitters 3.
- However, they differ in their pharmacokinetic and pharmacodynamic characteristics, with pregabalin being absorbed more rapidly and having a higher bioavailability than gabapentin 3.
- Pregabalin has a linear absorption profile, whereas gabapentin has a saturable absorption profile, making its pharmacokinetics less predictable 3.
Pharmacokinetic Advantages of Pregabalin
- Pregabalin has a faster absorption rate, with maximum plasma concentrations attained within 1 hour, compared to 3-4 hours for gabapentin 3, 4.
- Pregabalin has a higher bioavailability, with an absolute bioavailability of > or = 90%, compared to 60% for gabapentin at a dosage of 900 mg/day 3.
- Pregabalin is not metabolized by hepatic enzymes and does not inhibit the metabolism of other drugs, reducing the risk of drug interactions 3, 5.
Clinical Efficacy of Pregabalin and Gabapentin
- Both pregabalin and gabapentin have been shown to be effective in the treatment of neuropathic pain, partial seizures, and anxiety disorders 3, 5, 6, 4, 7.
- Pregabalin may be more effective than gabapentin in the treatment of postherpetic neuralgia and partial seizures, based on the magnitude of the reduction in seizure frequency 3.
- The combination of pregabalin and gabapentin may have a synergistic effect in pain control, without significant pharmacokinetic interactions 6.