Demodectic Mange in Cats

Both types of mange are characterized by itching and sores on the skin. Generalized forms of demodectic mange may be indicative of a more serious underlying condition in which the immune system is suppressed, such as feline leukemia or cancer.

Demodectic mange is an uncommon skin condition that is caused by two species of demodectic mites. Demodex cati is one species of demodectic mite that is normally found in the hair follicles on cats. Infections from D. cati are typically localized and are usually associated with immunosuppressive conditions. Infectious Demodex gatoi causes a contagious form of demodectic mange that may be localized to a specific area or affect the whole body.  D. gatoi is more commonly found in the southern states of America.

Symptoms can be nonspecific and may vary depending on the presence of any underlying conditions. While demodectic mange is not considered a life-threatening condition, you should seek immediate veterinary attention as soon as you notice any of the following symptoms in order to minimize your cat’s discomfort and pain.

• Crusty scabs or sores, usually around the head, ears, and neck
• Excessive, severe itching and grooming
• Signs of pain
• Hair loss

The primary cause of demodectic mange in cats is infection by demodectic mites. There are no age or sex predispositions for demodectic mange. However, demodectic mange caused by D. cati is more common in Siamese and Burmese cats. 

Demodectic mange caused by D. gatoi is more commonly diagnosed in the southern region of the United States, particularly Texas and Florida. Secondary causes of infection may be associated with a suppressed immune system.  Causes of suppressed immune systems may vary depending on the underlying condition.

Your vet will be able to make a tentative diagnosis based on a thorough physical examination and presentation of symptoms. Be sure to inform your vet of the extent and duration of your cat’s symptoms, as well as any relevant travel history.

Your vet will make a definitive diagnosis by taking skin scrapings and examining them under a microscope. Multiple skin scrapings may be required, as mites can be removed during grooming. D. cati mites are much easier to diagnose compared to D. gatoi. Additional diagnostic testing may be required to rule out underlying immunosuppressive conditions.

Treatment may vary depending on the species of mite present and the location of infection. Your vet will be able to advise you on a treatment plan based on your cat’s specific needs.

The main treatment method for demodectic mange is the use of lime-sulfur dips once every seven days for four to six weeks. Due to their popular aversion to bathing, cats are not fond of lime-sulfur dips.  Lime-sulfur dips also have an unpleasant smell and can cause discoloration of the coat. However, this is currently the most effective treatment and carries the lowest risk. 

Other treatments include oral doses of ivermectin and the topical treatment, selamectin. Another alternative treatment for demodectic mange is weekly injections of doramectin for up to three weeks. However, these treatments are prescribed less often due to safety reasons and their lack of efficiency in treating demodectic mange.

Other treatments may be required based on the presence of underlying conditions.

Recovery and prognosis may vary depending on the location of the infection and whether or not there are any underlying immunosuppressive conditions. Always follow your vet’s post-treatment instructions carefully. Always administer any prescribed medications exactly as directed for the full duration of the treatment period. Do not use any topical treatments or ointments made for human use unless explicitly instructed to do so by your vet. These may worsen the condition.

If you live in a multi-cat household, you should isolate any infected cats to reduce the spread of infection. Since demodectic mites are unable to survive in the environment, you will not need to disinfect furniture or carpets.

You will usually need to shampoo your cat using a cat-safe shampoo before applying the lime-sulfur concentrate. When you administer the lime-sulfur dips, you may benefit from having another person present to help you manage the cat. Your vet may prescribe the lime-sulfur dip in spray form to help minimize your cat’s stress during treatment. You should allow the solution to dry on the skin. Your vet will be able to provide further instructions on administering lime-sulfur dips.

Your vet will typically not schedule follow-up appointments for cases of idiopathic demodectic mange. In cats with underlying diseases, follow-up appointments will be scheduled as needed to monitor the condition. If you have any questions or if the condition does not appear to be improving despite treatment, contact your vet immediately.