Mixing DMSO with water is straightforward: measure out your desired ratio of DMSO to distilled water and combine them in a compatible container. The most important things to get right are the container material, the water quality, and the ratio, since each concentration behaves differently on skin. Here’s what you need to know to do it safely and effectively.
Choose the Right Container
DMSO is a powerful solvent, and it will dissolve or leach chemicals from certain plastics. That means the container you mix in matters just as much as what you’re mixing. DMSO is compatible with HDPE (high-density polyethylene), LDPE (low-density polyethylene), polypropylene, nylon, and Teflon. Glass is also a safe choice and is what many people prefer for storage.
Avoid PVC (both flexible and rigid), polycarbonate, and polysulfone containers entirely. DMSO will break these materials down and pull plastic compounds into your solution. Polystyrene has only moderate compatibility, so it’s best avoided too. If you’re unsure what a container is made of, check the recycling symbol on the bottom. HDPE is marked with a “2” and polypropylene with a “5.” When in doubt, use glass.
Use Distilled or Purified Water
Because DMSO penetrates skin so readily and can carry dissolved substances along with it, you want the cleanest water possible. Distilled or deionized water is the standard choice. Tap water contains chlorine, fluoride, trace minerals, and sometimes other contaminants that DMSO could potentially transport through your skin. This isn’t the place to cut corners.
Select the Right Grade of DMSO
DMSO comes in several grades, from technical (industrial) to USP (pharmaceutical) grade. For anything involving skin contact, USP-grade DMSO is what you want. It’s held to strict purity standards and is virtually odorless. Lower grades are byproducts of industrial processing and can contain distillates and contaminants that don’t dissolve freely in water. You can actually test this yourself: when USP-grade DMSO is added to water, it should mix completely without forming crystals or leaving residue. If it doesn’t mix cleanly, the purity is suspect.
How to Mix: Step by Step
The process itself is simple. Decide on your target concentration, measure the DMSO and distilled water separately, then combine them. You can measure by volume using graduated cylinders or syringes for accuracy.
For a 70% DMSO solution, combine 70 mL of DMSO with 30 mL of distilled water. For a 50/50 mix, use equal parts. Pour the DMSO into the container first, then add the water gradually.
One thing that surprises people: DMSO and water generate heat when mixed. This is a normal exothermic reaction. The container will feel noticeably warm, sometimes quite hot if you’re mixing larger volumes. This is expected and not a sign of a problem. Let the solution cool to room temperature before applying it to skin or storing it.
Why the Ratio Matters
The concentration of DMSO in your mixture directly affects how it interacts with skin. Research on skin permeability shows a clear threshold around 70% DMSO. Below that concentration, DMSO actually reduces the rate at which substances pass through the outer layer of skin. Above 70%, permeability increases significantly, and concentrations above 80% DMSO produce penetration rates that exceed what plain water achieves on its own.
This means diluting DMSO with more water doesn’t just make it weaker in a linear way. A 50% solution behaves quite differently from a 90% solution. The common concentrations people use and why:
- 90% DMSO / 10% water: Maximum penetration. Can cause more skin irritation, warmth, and itching. Often used for localized joint or muscle applications where deep absorption is the goal.
- 70% DMSO / 30% water: The most widely used ratio. Sits right at the threshold where skin permeability begins to increase, while being less irritating than higher concentrations. This is a common starting point.
- 50% DMSO / 50% water: A milder option. Penetration is reduced compared to 70%, but skin irritation is also lower. Sometimes preferred for sensitive areas or for people new to using DMSO.
If you’ve never used DMSO before, starting at 50% or 70% and observing how your skin reacts is a reasonable approach. Some redness, warmth, and a garlic-like taste in the mouth (DMSO is metabolized and you can taste it within minutes of skin application) are common responses, not signs of a problem.
Storage and Shelf Life
Store your mixed solution in a sealed glass or compatible plastic container at room temperature, away from direct sunlight. Pure DMSO has a freezing point around 19°C (66°F), so it can solidify in a cool room. Adding water lowers the freezing point, so diluted solutions stay liquid at lower temperatures. A 70% solution will remain liquid under normal household conditions.
Keep the container sealed when not in use. DMSO is hygroscopic, meaning it absorbs moisture from the air, which gradually changes your concentration over time. A tightly sealed container in a cabinet is ideal. Mixed solutions remain stable for months when stored properly, though making smaller batches you’ll use within a few weeks keeps the concentration most consistent.
Safety Basics for Handling
The single most important safety principle with DMSO is that it carries whatever is on your skin into your body. Before applying any DMSO solution, wash the area thoroughly with soap and water and let it dry completely. This removes lotions, fragrances, dirt, cleaning product residue, and anything else you don’t want transported through your skin.
Use the same logic for your hands when mixing. Wash them before handling DMSO. Don’t wear latex gloves, as DMSO can leach compounds from latex. Nitrile gloves are a better option if you want hand protection during mixing, though even some nitrile gloves contain additives. Clean, freshly washed bare hands on clean, dry skin is the simplest safe approach for small-volume mixing.
Work in a clean area with clean tools. Any measuring cups, syringes, or stirring rods should be glass, stainless steel, or compatible plastics. Rinse them with distilled water before use to remove any residue from previous cleaning products.