About 85% of patients suffer from phantom limb pain (PLP), which refers to the abnormal sensations like tingling, cramps, heat, etc. experienced the amputees in the amputated body part. Memantine is a clinically useful drug in many neurological disorders like Alzheimer's disease. It is a N-Methyl-d-aspartate (NMDA) receptor antagonist that has shown benefits in various pain syndromes. Loy B M et. al conducted a systematic review to estimate the evidence for the use of memantine in the treatment of acute and chronic phantom limb pain.

The articles from MEDLINE (1956 to May 2016) and Embase (1957 to May 2016) were explored that characterized the clinical outcomes of patients treated with memantine in PLP. As per the initial search, 185 studies and case reports were identified. Eight articles were considered after the final screening.

The benefits of using memantine in the treatment of acute PLP were revealed in one prospective study, a case report, and two case series. Nonetheless, four prospective studies failed to demonstrate the significant analgesic effects with memantine in chronic PLP that persisted for over 1 year. However, in all studies, memantine was proven to be well tolerated. 

Therefore, it culminates that memantine appears to be a reasonable approach in patients with a recent amputation or who have failed or cannot tolerate other analgesics. To further determine the role of memantine in the treatment and prevention of PLP and to identify the population most likely to gain benefit, additional research is required.