Nutmeg Extracts for Painful Diabetic Neuropathy: A Randomized, Double-Blind, Controlled Study

Abstract

Current treatment strategies for painful diabetic neuropathy (PDN) include oral medications, which are costly and may have adverse effects. Topical therapies have been used for PDN with some benefit. Nutmeg has certain properties that may be effective in ameliorating neuropathic pain. The purpose of this study was to determine whether topical nutmeg extracts can reduce pain or improve the quality of life in PDN sufferers. This study was a randomized, double-blind, placebo-controlled trial. It was conducted at a primary care center in Trinidad, Caribbean. Seventy-four (74) diabetic subjects who met criteria for painful neuropathy were recruited. Participants were randomized to receive either topical nutmeg extracts (NEMM; mace oil [2%], nutmeg oil [14%], methyl salicylate [6%], menthol [6%], and coconut oil) or placebo (MM; methyl salicylate [6%], menthol [6%], coconut oil, and alcohol). Outcome measures of pain and quality of life were assessed using the Brief Pain Inventory for Diabetic Painful Neuropathy and Neuropathic Pain Symptom Inventory. An intention-to-treat analysis was done for 24 male and 50 female subjects (30-85 years) with an average duration of diabetes of 11 years. Significant reductions in worst and average pain scores were seen within each group (p ≤ 0.001). Similarly significant reductions were also noted for interference with walking, sleep, and mood scores as well as burning, pins and needles, and tingling scores within each group (p<0.05). There were no statistically significant differences between both groups after 4 weeks for any outcome measure. In this trial topical, nutmeg extracts did not add to the improvements observed in PDN symptoms during 4 weeks treatment with preparations containing menthol and methyl salicylate. Further research designed to test the individual components of the topical therapies used in this study may clarify their benefit.