Peripheral neuropathy is most commonly caused by diabetes mellitus and neuropathy doubles the risk of amputation in diabetics.
Evening primrose oil is a source of gamma-linolenic acid (GLA.), which leads to more eicosanoids that dilate blood vessels in the diabetic. Eicosanoids also cause an improvement of nerve function as evidenced by improved nerve conduction testing. They prevent slow circulation due to platelet clumping. The suggested dose is 400 mg. per day in divided doses.
Acetyl-l-carnitine improves mitochondrial fatty acid oxidation and is produced by the human brain, liver, and kidneys. It increases acetylcholine production and improves phospholipid synthesis in cell membranes. In this study diabetic patients were given 2000 mg. per day of acetyl-l-carnitine, which resulted in a 39% reduction of pain and general improvement in the peripheral neuropathy. Suggested doses are 2000-3000 mg. per day in divided doses.
Alpha lipoic acid is a strong antioxidant that can regenerate other antioxidants and is used for treatment and prevention of neuropathy in diabetics. The use of alpha lipoic acid can cause hypoglycemia in controlled diabetics because it reduces insulin resistance. The suggested dose is 600 mg. three times a day.
The B vitamins folic acid, pyridoxine, and cyanocobalamine, which reduce homocysteine, are used in the treatment of diabetic neuropathy. High blood homocysteine levels increase the risk of development of peripheral neuropathy in diabetics nine fold. Therapeutic reduction of homocysteine blood levels reduces the severity of peripheral neuropathy.
Magnesium would be beneficial in peripheral neuropathy on theoretical grounds and has been shown to be of benefit in chronic pain of diverse origin.
Dehydroepiandrosterone (DHEA) levels tend to be low in diabetics and treatment with DHEA is believed to be beneficial in peripheral neuropathy. Further studies need to be done.
L-Arginine helps supply nitric oxide for wound healing and improves circulation, which can be of great benefit in diabetic peripheral neuropathy.
CONCLUSION: The supplements that have been shown to be beneficial in diabetic peripheral neuropathy are as follows: Evening primrose oil, acetyl-l-carnitine, alpha lipoic acid, folic acid, pyridoxine, cyanocobalamine, magnesium, DHEA, and l-arginine.
NOTE: Nerve conduction studies can be used to evaluate the condition of nerves in the arms and legs. Nerve conduction times (NCT) are studied by giving electric shocks to the nerves through the skin and calculating nerve conduction velocities. NCT studies can be used to follow the progress of peripheral neuropathy.
Chromium is a treatment for diabetes mellitus. Chromium deficiency can be the cause of peripheral neuropathy.