Health & Welfare: DMSO

Its uses and mode of action


DMSO (dimethyl sulfoxide) is one of those drugs caught up in the quagmire of FDA regulations. We have seen it being illegally sold in many health food, hobby, and hardware stores in southern California. It is being sold by mail order, as well, via display ads in major newspapers and magazines. Judging from the prices at which it is offered, much of this quasiillegal DMSO must be of industrial-solvent grade—which contains undesirable impurities such as dimethylsulfone, dimethylsulfide, and benzene—rather than the high-purity reagent, spectrophotometric (very pure DMSO for use as a solvent for substances to be analyzed by the selective absorption of ultraviolet, infrared, and visible light), or pesticide-quality (suitable for pesticide residue analysis) grades. DMSO is also available legally as an industrial solvent and as a prescription drug, RIMSO-50 (50 percent DMSO and 50 percent water). The prescription drug is approved by the FDA for the treatment of bladder cysts, and they warn that use of DMSO for any other condition may be dangerous.

DMSO has an almost legendary public reputation as a treatment for arthritis and sports injuries. Yet, because so much of that reputation has stemmed from anecdotal accounts (which can provide leads but cannot be considered proof of anything), because there is no patent protection available for DMSO (and consequently little incentive for a private firm to invest in DMSO research), and because the mechanisms of its action were not known until recently, DMSO use has been considered controversial. Now, however, researchers have discovered a major mechanism of its action which explains much if not most, of DMSO's beneficial effects in many cases of pain and swelling of arthritis and in reducing time required for the healing of injuries. At present, this drug is being used by millions of Americans, including sports teams, where injuries can represent a lot of lost income.

In 1974 McCord reported his studies indicating that free radicals are responsible for arthritis. Free radicals are molecules or atoms with an unpaired (free) electron, and they are extremely reactive. They are also ubiquitous in living organisms. All air-breathing organisms on this planet contain special protective enzymes (such as zinc-containing superoxide dismutase and selenium-containing glutathione peroxidase) and antioxidants (nutrient factors that both destroy free radicals and block uncontrolled oxidation reactions that result in their formation), including vitamins A, C, E, B-1, B-5, B-6, the amino acid cysteine, and the minerals zinc and selenium. Free radicals are now considered by many scientists to be major causative factors in aging, cardiovascular disease, cancer, emphysema, and many other conditions, including arthritis, dandruff, and acne pimples.

Radiation sickness is an example of a pure free radical disease. Radiation kills by creating free radicals, which then attack cell membranes, fats, DNA, RNA, and proteins. Dr. Denham Harman of the University of Nebraska, who originated the free radical theory of aging, calls free radicals "internal radiation." Free radicals arising out of exposure to external radiation such as x-rays represents only a very small part of the total amount of free radicals to which we are exposed. The rest are created during normal metabolism (free radical reactions are a necessary part of energy production) and during the breakdown of peroxidized fats (rancid fats created in the body by exposure of these fats to oxygen or other oxidizers). Although we do contain a generous supply of protective enzymes, the protection is not perfect and, over time, much damage is done.

There are different types of free radicals. McCord found that superoxide radicals and hydrogen peroxide (a common byproduct of metabolism) must both be present in order to destroy the lubricating fluids and membranes in our joints. The enzyme superoxide dismutase (SOD) can protect our joints and other tissues against superoxide radicals; injections of SOD into arthritic joints have sometimes had dramatic effects. The enzyme catalase, which breaks down hydrogen peroxide to harmless products, also provides protection. According to McCord's studies, the agents that actually attack the lubricants in our joints are hydroxyl radicals, the nastiest type of free radical known. They are more reactive than fluorine and are so reactive that they can attack the "inert" or "noble" elemental gas xenon.

This is where DMSO comes in. DMSO is not a joint lubricant. DMSO is not an analgesic (pain deadener). Arthritis experiments based on these hypotheses were doomed to failure. DMSO is a powerful scavenger of hydroxyl free radicals. Inositol is another such scavenger, though not as powerful as DMSO. By removing the hydroxyl radicals, DMSO provides excellent protection to joint-lubricating fluids and membranes.

That isn't the end of the story, however. After chemically reacting with hydroxyl radicals, DMSO is itself converted to a free radical—not as dangerous as the hydroxyl radicals, but a free radical, nevertheless. Because of this, it is important to use DMSO in conjunction with other antioxidants, like vitamins C, E, and the others mentioned above. Large repeated doses of DMSO have caused cataracts in the eyes of experimental rabbits. Rabbits have relatively poor natural antioxidant enzyme protection compared to humans and, in experiments, could not adequately protect themselves from all those DMSO free radicals. The DMSO radicals oxidized the amino acids cysteine and methionine to their sulfoxide, sulfone, and disulfide forms, impairing the transparency of the lens and cornea in the rabbits. It is important, therefore, that if you choose to use DMSO you be sure it is very pure, use it externally on limited areas of the body, and take plenty of supplemental antioxidant nutrients.

Where do sports injuries come in? We now know that free radical damage is an important part of such injuries. When injuries occur, blood vessels leak blood into surrounding tissues. As the red blood cells hemolyze—that is, break down—they release copper and iron, which are very powerful catalysts of free radical reactions. The blue, black, yellow, and other colors you see in a crushing injury are a result of free radical attacks. The browning of freshly cut fruits such as apples and bananas is another example of free radical reactions, which also damage cell membranes and cause softening. We've found in our personal use that if you apply DMSO quickly enough (preferably in the first half hour, two to four hours at most) to a crushing injury, the colors never form and swelling is greatly reduced.

Dr. Harry Demopoulos of New York University and his coworkers found that prompt injection of DMSO reduced the degree of paraplegia occurring in cats that had been subjected to experimental crushing injuries of the spinal cord. Concussion damage to nerves is principally due to free radicals catalyzed by the leaking copper and iron. Using an electron spin resonance spectrometer (an electronic instrument that identifies and counts free radicals), he found that free radical activity increased to over 100,000 times normal several hours after the injury. Perhaps in the future, we will see DMSO in the emergency medical kits of paramedics, as well as sports physicians and veterinarians.

References to this column are available. Send a stamped self-addressed envelope to this publication, referring to "DMSO."


Q: I live in a small town that doesn't have a health food store. The local drug store carries the usual, run-of-the-mill vitamins but not the more "exotic" nutritional supplements you mention in your columns. Do you have any suggestions about how one might obtain these?

A: Your best sources after local vitamin/nutrient shops are mail-order firms. There are many such companies, although the more "exotic" the nutrient, the more searching you may have to do to find a company offering it. Here are a few mail-order companies that offer a wide variety of vitamins, amino acids, minerals, and other nutrients. We have no financial involvement in any of these companies and we accept no responsibility for dealings with them.

vitamin C crystals

Bronson Pharmaceuticals
4526 Rinetti Lane
La Canada, CA 91011

vitamins, amino acids
(mostly supplied in formulations)

Alacer Corp.
Box 6448
Buena Park, CA 90622

empty gelatin capsules

Pure Planet Products
1025 N. 48th St.
Phoenix, AZ 85008

vitamins, amino acids,
food additives

Vitamin Research Products
1961-D Old Middlefield Way
Mountain View, CA 94043

Durk Pearson and Sandy Shaw are consulting scientists, authors, and TV personalities.

Copyright © 1981 by Durk Pearson and Sandy Shaw.