Memantine

This article is a stub.

Memantine is an oral NMDA antagonist. It's use in chronic neuropathic pain is still not proven and hence is off-label (only approved for Alzheimer's disease)

It is an amantadine derivative, and acts as an uncompetitive NMDA receptor antagonist but exhibits lower affinity and faster dissociation kinetics compared to ketamine, potentially interfering less with normal synaptic transmission and offering a better tolerability profile.^[1] It aims to dampen the excessive glutamatergic neurotransmission and subsequent calcium influx that drives neuronal hyperexcitability in CS.

A systematic review in 2019 assessing its efficacy for chronic pain treatment (pooling studies on neuropathic conditions and fibromyalgia) yielded disappointing results, finding limited and uncertain evidence with no significant overall difference in end pain scores compared to placebo.^[2]^[3]

The biggest trial was the only trial on fibromyalgia with 63 patients over 6 months. Memantine was superior to placebo with an NNT of 6.2.^[4]

Dosing: week 1 5mg daily, week 2 10mg daily, week 3 15mg daily, week 4 20mg daily.

Dizziness is the most common side effect seen in 1/3 of patients. Gastrointestinal side effects like nausea and diarrhea may also occur.

Resources

Memantine - Nair 2019.pdf - 313 KB (f)

Memantin - kurian 2019.pdf - 1.68 MB (f)

NMDA antagonists - aiyer 2017.pdf - 4.4 MB (f)

Memantine vs placebo for fibromyalgia - Olivan-Blazquez 2014.pdf - 1.15 MB (f)

References

↑ Nair, Abhijit S.; Sahoo, Rajendra Kumar (2019-01). "Efficacy of Memantine Hydrochloride in Neuropathic Pain". Indian Journal of Palliative Care (in English). 25 (1): 161. doi:10.4103/IJPC.IJPC_189_18. PMID 30820121. Check date values in: |date= (help)
↑ Pickering, Gisèle; Morel, Véronique (2018-02). "Memantine for the treatment of general neuropathic pain: a narrative review". Fundamental & Clinical Pharmacology (in English). 32 (1): 4–13. doi:10.1111/fcp.12316. ISSN 0767-3981. Check date values in: |date= (help)
↑ Kurian, Rouvin; Raza, Kazim; Shanthanna, Harsha (2019-08). "A systematic review and meta-analysis of memantine for the prevention or treatment of chronic pain". European Journal of Pain (London, England). 23 (7): 1234–1250. doi:10.1002/ejp.1393. ISSN 1532-2149. PMID 30848504. Check date values in: |date= (help)
↑ Olivan-Blázquez, Bárbara; Herrera-Mercadal, Paola; Puebla-Guedea, Marta; Pérez-Yus, Mari-Cruz; Andrés, Eva; Fayed, Nicolas; López-Del-Hoyo, Yolanda; Magallon, Rosa; Roca, Miquel; Garcia-Campayo, Javier (2014-12). "Efficacy of memantine in the treatment of fibromyalgia: A double-blind, randomised, controlled trial with 6-month follow-up". Pain. 155 (12): 2517–2525. doi:10.1016/j.pain.2014.09.004. ISSN 0304-3959. Check date values in: |date= (help)

[1] Nair, Abhijit S.; Sahoo, Rajendra Kumar (2019-01). "Efficacy of Memantine Hydrochloride in Neuropathic Pain". Indian Journal of Palliative Care (in English). 25 (1): 161. doi:10.4103/IJPC.IJPC_189_18. PMID 30820121. Check date values in: |date= (help)

[2] Pickering, Gisèle; Morel, Véronique (2018-02). "Memantine for the treatment of general neuropathic pain: a narrative review". Fundamental & Clinical Pharmacology (in English). 32 (1): 4–13. doi:10.1111/fcp.12316. ISSN 0767-3981. Check date values in: |date= (help)

[3] Kurian, Rouvin; Raza, Kazim; Shanthanna, Harsha (2019-08). "A systematic review and meta-analysis of memantine for the prevention or treatment of chronic pain". European Journal of Pain (London, England). 23 (7): 1234–1250. doi:10.1002/ejp.1393. ISSN 1532-2149. PMID 30848504. Check date values in: |date= (help)

[4] Olivan-Blázquez, Bárbara; Herrera-Mercadal, Paola; Puebla-Guedea, Marta; Pérez-Yus, Mari-Cruz; Andrés, Eva; Fayed, Nicolas; López-Del-Hoyo, Yolanda; Magallon, Rosa; Roca, Miquel; Garcia-Campayo, Javier (2014-12). "Efficacy of memantine in the treatment of fibromyalgia: A double-blind, randomised, controlled trial with 6-month follow-up". Pain. 155 (12): 2517–2525. doi:10.1016/j.pain.2014.09.004. ISSN 0304-3959. Check date values in: |date= (help)

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