Gentacalm Topical Spray is a prescription veterinary medication used to treat bacterial skin infections in dogs. It combines an antibiotic (gentamicin sulfate) with a corticosteroid to fight infection while reducing the inflammation, redness, and itching that come with it. The spray is manufactured by Dechra Veterinary Products and is FDA-approved specifically for use in dogs.
How Gentacalm Works
The spray contains two active components that work together. Gentamicin sulfate is an antibiotic that kills the bacteria causing the skin infection. The corticosteroid component tackles the symptoms your dog is actually suffering from: swelling, itching, and irritation. This combination approach means the spray treats both the underlying infection and the discomfort it causes, which can also help break the itch-scratch cycle that makes skin infections worse.
How It’s Applied
The standard dosing is two pumps of the spray head directly onto the affected skin, repeated two to four times daily for seven days. The metered spray design delivers a consistent dose with each pump, making application straightforward. Your vet will determine the exact frequency based on the severity of your dog’s infection.
Because the spray contains a corticosteroid, it’s important to stick to the prescribed treatment length. Stopping too early can let the bacterial infection bounce back, while using it longer than directed increases the chance of side effects from corticosteroid absorption through the skin.
Side Effects to Watch For
In clinical testing, Gentacalm was well tolerated when applied to dogs’ skin, including on abraded (broken) skin. No treatment-related skin damage was observed in those studies. Local irritation at the application site is uncommon.
The bigger concern is systemic absorption of the corticosteroid component, especially with prolonged use or overuse. In safety studies, higher doses produced changes in the adrenal glands, liver, and kidneys, all of which were dose-related and considered reversible once treatment stopped. Signs that your dog may be absorbing too much corticosteroid include increased thirst, increased urination, weight gain, or fluid retention.
If your dog licks the treated area and ingests the product, watch for those same signs of corticosteroid overdose, along with loss of appetite, vomiting, or diarrhea. Prolonged overexposure can also suppress the immune system, making your dog more vulnerable to other infections.
Dogs That Should Not Use It
Gentacalm should not be used in dogs with a known hypersensitivity to any of its ingredients. If your dog develops signs of an allergic reaction (increased redness, swelling, or hives at the application site), treatment should be stopped.
The corticosteroid component also makes this spray unsuitable for pregnant dogs. Corticosteroids given during pregnancy have been linked to premature labor, fetal death, and birth defects including cleft palate and limb deformities in dogs. If your dog is pregnant or may become pregnant, your vet will choose a different treatment.
It’s also worth noting that Gentacalm is approved only for dogs. It has not been evaluated or approved for use in cats or other animals. Cats are particularly sensitive to certain antibiotics and corticosteroids, so this product should never be shared between pets of different species.
What to Expect During Treatment
Most dogs show improvement within the first few days as the antibiotic begins clearing the bacterial infection and the corticosteroid brings down inflammation. The full seven-day course is important even if the skin looks better sooner, because bacteria can persist beneath visibly healing skin.
After treatment ends, your dog’s body needs to readjust its own natural steroid production, which the corticosteroid component may have temporarily suppressed. This is another reason not to extend use beyond what your vet prescribes. If your dog’s skin infection hasn’t cleared after seven days, a follow-up visit can help determine whether a different treatment approach is needed.