From the Guidelines
Gabapentin is considered an anticonvulsant medication with analgesic properties, rather than a traditional non-opioid analgesic, and is commonly used to treat neuropathic pain conditions, including diabetic neuropathy, postherpetic neuralgia, and fibromyalgia 1.
Key Points
- Gabapentin works by binding to calcium channels in the nervous system, reducing the release of excitatory neurotransmitters involved in pain signaling 1.
- Its mechanism differs from traditional non-opioid analgesics like NSAIDs, which work by inhibiting prostaglandin synthesis 1.
- Gabapentin is typically prescribed at doses ranging from 300mg to 3600mg daily, divided into three doses, with side effects including dizziness, drowsiness, and peripheral edema 1.
- Unlike opioids, gabapentin does not bind to opioid receptors and has a lower risk of respiratory depression, though it still requires careful monitoring for potential misuse 1.
Clinical Considerations
- The use of gabapentin for neuropathic pain conditions is supported by strong evidence, with a number needed to treat (NNT) value of 6-7 for moderate benefit 1.
- Gabapentin is considered a first-line treatment for neuropathic pain, along with other anticonvulsants like pregabalin 1.
- Careful titration and monitoring are necessary to minimize side effects and optimize pain relief 1.
From the FDA Drug Label
The precise mechanisms by which gabapentin produces its analgesic and antiepileptic actions are unknown. Gabapentin is structurally related to the neurotransmitter gamma-aminobutyric acid (GABA) but has no effect on GABA binding, uptake, or degradation In vitro studies have shown that gabapentin binds with high-affinity to the α2δ subunit of voltage-activated calcium channels; however, the relationship of this binding to the therapeutic effects of gabapentin is unknown.
Gabapentin is an analgesic, as it is mentioned that gabapentin produces analgesic actions, although the precise mechanisms are unknown. There is no information about gabapentin being "non-opened" in the provided drug labels 2 2.
From the Research
Gabapentin as an Analgesic
- Gabapentin is used to treat diabetic peripheral neuropathic pain (DPNP) and has been compared to other medications such as duloxetine and pregabalin in terms of efficacy and tolerability 3, 4, 5, 6, 7.
- Studies have shown that gabapentin, duloxetine, and pregabalin are effective in reducing pain severity in patients with DPNP, with some variations in tolerability and adverse effects 3, 5, 6.
- A meta-analysis found that duloxetine, pregabalin, and gabapentin were superior to placebo in reducing 24-hour pain severity, with some differences in response rates and tolerability 5.
Gabapentin in Combination with Other Medications
- Gabapentin has been used in combination with duloxetine for the treatment of DPNP, with results showing that the combination is generally safe and tolerable, although with some increased risk of adverse effects such as nausea and hyperhidrosis 3, 6.
- A study found that the combination of duloxetine and gabapentin was non-inferior to pregabalin in terms of pain reduction, although with some differences in adverse effects 6.
Efficacy of Gabapentin Compared to Other Medications
- A study found that duloxetine was non-inferior to pregabalin in terms of pain reduction, and that gabapentin was less effective than duloxetine in reducing pain severity 7.
- Another study found that gabapentin was less potent than morphine in reducing neuroma pain, although it was effective in reducing mechanical allodynia 4.