DMSO cream is a topical product containing dimethyl sulfoxide, a colorless liquid solvent that penetrates skin unusually well and carries other substances with it. It’s sold over the counter in concentrations ranging from 10% to 90% and marketed primarily for joint and muscle pain, though its only FDA-approved use in humans is for a bladder condition called interstitial cystitis, where it’s delivered directly into the bladder rather than applied to the skin. The cream form you’ll find in stores or online is considered a supplement, not a regulated medication.
How DMSO Penetrates the Skin
DMSO’s molecular structure is what makes it unusual. It has both a water-attracting group and two fat-attracting groups, giving it the ability to interact with both watery and oily environments. Your skin’s outermost layer, the stratum corneum, is a tightly packed barrier of proteins and fats designed to keep things out. DMSO disrupts that barrier in a concentration-dependent way: at lower concentrations it loosens the fatty layer, making it more fluid; at higher concentrations it can actually create tiny water-filled pores and pull lipid molecules out of position.
This penetration creates what researchers describe as a “push-pull effect.” DMSO moves through the skin faster than most other compounds and increases the solubility of whatever is mixed with it. It essentially builds a reservoir in the skin that pulls other molecules along for the ride. That’s why DMSO has long been used in laboratory and pharmaceutical research as a carrier solvent, helping poorly soluble drugs get where they need to go.
What People Use It For
Most people buying DMSO cream are looking for pain relief, particularly for osteoarthritis, muscle strains, sprains, or general joint soreness. It’s also marketed for skin conditions, wound healing, and inflammation. The idea is that DMSO’s anti-inflammatory properties, combined with its deep skin penetration, deliver relief directly to the painful area.
Laboratory research does show DMSO can suppress inflammatory signaling molecules in blood cells and reduce markers of autoimmune arthritis in experimental settings. Translating that into meaningful pain relief for real patients has been harder to demonstrate.
What the Evidence Actually Shows
The clinical evidence for DMSO cream as a pain reliever is underwhelming. A meta-analysis examining DMSO and its related compound MSM for knee osteoarthritis found a pain reduction of only 6.3 mm on a 100 mm pain scale compared to placebo. That difference was not clinically meaningful, meaning most patients wouldn’t notice it.
Individual study results have been mixed. One trial from 1995 found a statistically significant 64.5% reduction in pain with loading (weight-bearing) for DMSO versus 46.5% for placebo, a real but modest advantage. A larger 2004 trial found no difference at all between DMSO and placebo, with an effect size of zero. The Mayo Clinic states plainly that claims of DMSO’s effectiveness for arthritis, muscle injuries, burns, wounds, and skin infections “have not been proven.”
The gel formulation studied for osteoarthritis typically uses a 25% concentration. Products sold without a prescription vary widely, and higher concentrations do not necessarily mean better results. They do, however, increase the risk of side effects.
Side Effects and the Garlic Problem
The most distinctive side effect of DMSO is the smell. Your body metabolizes part of the compound into dimethyl sulfide, a volatile gas you exhale through your lungs. This produces a garlic- or oyster-like odor on your breath that can last for hours. A systematic review of adverse reactions found halitosis reported across 29 studies, and in five of those studies patients quit treatment specifically because of the smell. It’s not something you can mask with mouthwash since the odor comes from your lungs, not your mouth.
Beyond the odor, the most common side effects fall into two categories. Skin reactions, especially a local burning sensation at the application site, were reported in 13 studies. Gastrointestinal symptoms, particularly nausea and vomiting, were the other frequent complaint.
Why Skin Cleanliness Matters
Because DMSO is so effective at carrying substances through the skin barrier, anything on your skin when you apply it can potentially get pulled into your body. This includes lotions, perfumes, sunscreen, dirt, cleaning products, or chemical residues. Product labels instruct users to wash the application area with warm water and apply only to clean, intact skin. A patch test before first use is also recommended to check for sensitivity.
This carrier property also raises concerns about applying DMSO alongside other topical medications. If you’re using a prescription cream or ointment on the same area, DMSO could increase how much of that drug gets absorbed, potentially pushing it to levels your body wasn’t meant to receive. The same principle that makes DMSO useful in pharmaceutical research makes it unpredictable when layered with other products.
The One FDA-Approved Use
The only condition for which DMSO has full FDA approval is interstitial cystitis, a chronic bladder condition causing pain, pressure, and frequent urination. In that context, a purified medical-grade solution is instilled directly into the bladder by a healthcare provider. This is an entirely different delivery method and concentration from the creams sold as supplements, and the two should not be conflated.
Over-the-counter DMSO creams are regulated as supplements or cosmetics, not as drugs. That means manufacturers don’t have to prove they work before selling them, and product quality, purity, and concentration can vary between brands. If you’re considering DMSO cream for pain, this regulatory gap is worth keeping in mind: what’s in the jar may not match what’s on the label, and even if it does, the clinical evidence for pain relief remains thin.