DMSO (dimethyl sulfoxide) is produced by chemically oxidizing dimethyl sulfide, a byproduct of wood pulp processing. This is an industrial chemical process that requires specialized equipment, hazardous reagents, and precise temperature control. It cannot be safely or practically made at home, and attempting to do so poses serious risks of explosion, toxic gas exposure, and chemical burns.
How DMSO Is Made Industrially
The core chemistry behind DMSO production is straightforward in principle: you take dimethyl sulfide (DMS) and add an oxygen atom to its sulfur. In practice, industrial manufacturers use powerful oxidizing agents like nitrogen dioxide, nitric acid, or pure oxygen to drive this reaction. The process was first demonstrated in 1867 by the Russian chemist Alexander Saytzeff, who used concentrated nitric acid to oxidize dimethyl sulfide.
Today, the most common industrial method reacts dimethyl sulfide with nitrogen dioxide in a carefully controlled gas-liquid reaction. The speed and completeness of this reaction depend heavily on how well the gas mixes into the liquid, which is why manufacturers use specialized reactor vessels designed to maximize contact between the two phases. The raw product that comes out of this reaction is a crude DMSO solution containing water, unreacted starting materials, and various byproducts that must be removed.
Purification and Grading
Crude DMSO is purified through distillation, but this step is one of the most dangerous parts of the entire process. DMSO boils at 189°C, and as it approaches that temperature, it can rapidly decompose in an uncontrollable chain reaction. The decomposition is autocatalytic, meaning the byproducts it generates (hydrogen, methane, and carbon dioxide gases) accelerate further decomposition, creating a runaway reaction that can cause an explosion.
To manage this risk, industrial producers typically distill DMSO under vacuum, which lowers the boiling point and reduces the temperature needed. Even under vacuum, reboiler temperatures of 120 to 150°C are common for separating DMSO from water. This requires pressure-rated equipment, continuous temperature monitoring, and safety systems that can vent or quench a runaway reaction. A 1985 explosion at a waste treatment plant distilling DMSO killed one worker and injured another, and similar incidents have been documented repeatedly over the decades.
The final product is graded by purity. Pharmaceutical-grade DMSO undergoes additional purification steps and quality testing to ensure it meets strict standards. Industrial and veterinary grades are less rigorously purified and may contain impurities that are harmless in their intended applications but potentially dangerous if applied to human skin or tissue.
Why DIY Production Is Impractical
Every stage of DMSO synthesis involves materials and conditions that are genuinely dangerous outside a professional setting. Dimethyl sulfide, the starting material, is a volatile, flammable liquid with an intensely foul smell (it’s what gives rotting cabbage its odor). It’s toxic by inhalation and has a flash point of negative 38°C, meaning it can ignite well below freezing temperatures. The oxidizing agents used to convert it, particularly nitrogen dioxide and concentrated nitric acid, are corrosive, toxic, and can react violently with organic materials.
Even if you could somehow carry out the reaction, the purification step is where the real danger lies. Without vacuum distillation equipment rated for the pressures and temperatures involved, heating crude DMSO is essentially heating an explosion risk. A wide range of common contaminants, including acids, bases, and leftover oxidizing agents, can trigger the autocatalytic decomposition at temperatures lower than expected.
There’s also a fundamental quality problem. DMSO is a powerful solvent that penetrates skin within seconds, carrying dissolved substances directly into the bloodstream. Any impurity in a homemade batch, whether from the reaction itself, the containers used, or incomplete purification, would be transported through the skin along with the DMSO. You would have no way to verify purity without analytical chemistry equipment like gas chromatography.
What the FDA Actually Approves DMSO For
Despite widespread interest in DMSO for pain relief, inflammation, and skin conditions, it has only one FDA-approved use in humans: treating interstitial cystitis, a chronic bladder condition. In that application, a 50% solution is instilled directly into the bladder by a healthcare provider and left for fifteen minutes, repeated every two weeks until symptoms improve.
Claims that DMSO effectively treats arthritis, muscle strains, bruises, burns, wounds, skin infections, or neurological conditions have not been proven. The Mayo Clinic explicitly notes that industrial and veterinary preparations of DMSO must not be used by humans because their unknown purity can cause serious harm.
Buying DMSO Safely
Pharmaceutical-grade DMSO is available by prescription for its approved use. For other purposes, many people purchase DMSO labeled as 99.9% pure from chemical suppliers or health product retailers. If you choose to buy DMSO, the single most important factor is purity grade. Look for products that specify pharmaceutical or reagent grade rather than industrial or technical grade. Reagent-grade DMSO from established chemical suppliers (the same companies that supply research laboratories) offers verified purity with a certificate of analysis.
Because DMSO pulls anything on your skin’s surface into your body, always apply it to clean, dry skin free of lotions, sunscreen, or any other product. Use glass containers for storage, as DMSO can dissolve or leach chemicals from certain plastics. The solvent’s ability to penetrate skin is the very property that makes contamination so dangerous, whether from an impure product or from substances on the skin at the time of application.