By Dr. Jennifer Coates, DVM
Demodex cati is a normal resident of feline skin. Mange results when a cat’s immune system is not able to hold the numbers of mites in check. If your cat has been diagnosed with demodectic mange, this is what you can expect to happen next:
- Medication: Lime sulfur dips, oral ivermectin or milbemycin, injectable doramectin, or topical moxidectin.
What to Expect at the Vet’s Office
Demodectic mange in cats is often best treated with lime sulfur dips. Dips should be repeated once or twice a week for at least six weeks or until two consecutive skin scrapings or other diagnostic tests are negative. Other treatment options are available when dips are not appropriate but are associated with an increased risk of treatment failure and/or side effects. Ivermectin and milbemycin can be given orally, doramectin can be given by injection, and moxidectin can be applied topically.
Oftentimes veterinarians will perform skin scrapings on a weekly basis to monitor the cat’s response to treatment.
Two different species of Demodex mite (Demodex cati and Demodex gatoi) can cause mange in cats. Demodex cati is a normal resident of feline skin. Mange results when a cat’s immune system is not able to hold the numbers of mites in check. If your cat has been diagnosed with Demodex cati, your veterinarian may need to perform additional tests to look for an underlying disease that is compromising your cat’s immune system.
What to Expect At Home
Lime sulfur dips are given once or twice a week. They are extremely smelly and can stain clothing, jewelry, etc. While it is possible to give cats lime sulfur dips at home, many owners choose to have the dips performed at the veterinary clinic to avoid the mess and stress associated with the procedure. Cats are not wetted down prior to being dipped, and the lime sulfur is not rinsed away but allowed to dry on the skin and fur.
The typical schedule for alternative treatments for demodectic mange in cats are as follows:
- ivermectin and milbemycin by mouth once a day
- doramectin by injection once a week
- moxidectin applied to the skin as a spot-on once every 7-14 days
Improvement is usually evident within three weeks of the start of therapy. If a cat’s condition is not any better at this point, a different treatment option should be considered.
Questions to Ask Your Vet
Demodex gatoi (but not Demodex cati) can be contagious between cats. If you have more than one cat in your home, ask your veterinarian if they all need to be treated for mange.
If your cat’s demodectic mange does not respond to treatment as expected or becomes a recurring problem, he or she may have an underlying, immunosuppressive health problem. Some medications can also have an adverse effect on the immune system. Ask your veterinarian if either of these possibilities could be to blame for your cat’s continued struggle with demodectic mange.
Possible Complications to Watch For
Cats undergoing lime sulfur dips should be watched for signs of worsening skin irritation (e.g., redness or itchiness). Ivermectin and milbemycin can cause vomiting, diarrhea, and neurologic signs. Cats taking ivermectin diluted in propylene glycol can develop weakness, lethargy, and rapid breathing associated with anemia and should have a red blood cell count taken regularly to monitor for this complication.
Most cats with Demodex gatoi can be cured with appropriate treatment. When a cat has Demodex cati due to a chronic immunosuppressive condition or medication use that cannot be discontinued, maintenance therapy may be necessary to prevent relapses of demodectic mange.
Image: Jorg Hackemann / Shutterstock