DMSO (Dimethyl Sulfoxide) Cream & Gel

Dimethyl sulfoxide, usually shortened to DMSO, is a clear, colorless liquid first produced as a by-product of paper making. It dissolves an unusually wide range of substances, mixes with water, and passes through skin within minutes, carrying dissolved material with it. Those properties are why it has been studied as a medicine since the 1960s and why it is also treated with care: whatever is on the skin can travel inward with it.

In the United States the only FDA-approved DMSO product is Rimso-50, a 50% solution that a clinician instills into the bladder for the symptoms of interstitial cystitis. DMSO is also the carrier in Pennsaid, an approved diclofenac solution for knee osteoarthritis, where it makes up 45.5% of the product. No DMSO cream, gel, or solution is manufactured for direct use on the skin, so when a prescriber orders one, Bayview compounds dimethyl sulfoxide USP as a 10% topical gel or a 50% topical cream. These compounded preparations are not FDA-approved, their use is off-label, and a valid prescription is required. Bayview compounds this as part of our pain management line.

How does it work?

DMSO is a small, polar solvent that moves through the outer layer of skin and increases the passage of other molecules with it, which is why it is used as a penetration enhancer in Pennsaid and in custom topical preparations (Capriotti and Capriotti, 2012). On its own it has been reported to scavenge hydroxyl free radicals, to reduce local inflammation, and to slow conduction in small pain fibers, which is the basis for its study in painful and inflamed joints and soft tissue (Capriotti and Capriotti, 2012). In the body it is broken down to dimethyl sulfone and dimethyl sulfide, and the sulfide is what produces the garlic-like breath odor (DailyMed, Rimso-50 label).

What is it used for?

Prescribers most often order topical DMSO for localized musculoskeletal pain and inflammation: an osteoarthritic knee or hand, a sprain or strain, tendinitis, or bursitis. It is also ordered as a vehicle, added to a custom cream so that another ingredient reaches deeper tissue. The evidence for DMSO by itself is thin. A systematic review of the randomized trials in knee osteoarthritis found that two of four DMSO trials reported less pain than the comparator, but judged all of them to be of poor methodology, with possible unblinding from the odor and uncertain dose and duration, and concluded that no definitive conclusion could be drawn (Brien et al., 2008). The approved uses of DMSO, the bladder instillation for interstitial cystitis and the vehicle in Pennsaid, are for different routes and products (DailyMed, Rimso-50 label; FDA, Pennsaid label). Your prescriber decides whether topical DMSO fits your situation.

Gel or cream?

The 10% gel is the lighter, lower-strength option and dries quickly; the 50% cream is the strength most prescribers ask for and is closer to the concentration of the approved bladder solution. Both come in a metered pump so that each press delivers about the same amount. Higher strengths are more likely to redden, dry, or irritate the skin, which is one reason a prescriber may start with the gel. Your prescriber selects the form and strength; see the strengths section for what Bayview compounds.

How is it used?

Wash and dry the area first and apply nothing else to it: no other cream, lotion, sunscreen, or insect repellent, because DMSO can carry it through the skin. Apply a thin layer to the painful area as often as your prescriber directed, usually two or three times a day, and let it dry without covering it unless you were told to. Wash your hands afterward. Expect a garlic-like taste within minutes and a matching odor on your breath and skin that can last up to three days; it fades once treatment stops. Do not apply it near the eyes, to broken skin, or over a large area of the body.

Side effects & safety

The most common effects are the garlic-like taste and odor, and skin reactions at the site: dryness, redness, itching, warmth, and burning. In the Pennsaid trials, where DMSO is 45.5% of the product, dry skin at the application site was reported by about a third of patients, and contact dermatitis, sometimes with blisters, occurred with long-term use (FDA, Pennsaid label). Stronger preparations and covering the area with a dressing make irritation more likely.

Who should not use it?

Do not use DMSO if you are allergic to it. Avoid it on broken, infected, or freshly shaved skin, near the eyes, or under a dressing unless your prescriber directed otherwise. Talk with your prescriber before using it if you take a blood thinner or other medicines whose effect could be increased, if you have a history of eye problems, or if you are pregnant or breastfeeding: the approved labeling says DMSO should be used in pregnancy only if the potential benefit justifies the risk, and safety in children has not been established. Do not substitute industrial or veterinary DMSO bought online; its impurities travel through the skin as readily as the DMSO does.

How should it be stored?

Store as directed on your label, at room temperature away from heat and light, with the pump closed, and keep it out of the reach of children and pets. Do not use it after the beyond-use date, and dispose of unused medication as directed.

Why is this compounded?

The only FDA-approved DMSO product is the 50% bladder solution, and the only approved topical product containing DMSO uses it as a vehicle for diclofenac. When a prescriber wants DMSO itself on the skin, at 10% or 50%, alone or as the base for other ingredients, compounding is the only way to prepare it. As a 503A compounding pharmacy, Bayview prepares each order in small batches under USP standards, pursuant to a prescription for an individual patient. We do not supply it as clinic or office stock, that is the role of a 503B outsourcing facility, which Bayview is not. Compounded preparations are not FDA-approved. Related preparations include Diclofenac Gel, Topical Pain Cream, and Lidocaine Cream & Ointment. The full list is in our compounded medications catalog.