Alopecia, or 'hair loss' in cats is a common skin disorder of cats which occurs in all ages from newborn kittens (hormonal alopecia) to aged cats (hypothyroidism). The most common causes of alopecia in cats are atopy, fleas and food allergies.
- Allergies/Immune mediated
- Drug induced
- - Reactions have been associated with vaccines, ivermectin, praziquantel, antibiotics and glucocorticoids. Lesions are present at sites where injections are given. Therapy is usually not required. Hair regrowth may take several months to a year. In some cases the alopecia is permanent.
- - Trichorrhexis nodosa
- Psychological (psychogenic) licking
- - Squamous cell carcinoma - sores on tips of ears, nose and around the edges of eyelids. Most common in white cats.
- - Pancreatic paraneoplastic alopecia
- - Paraneoplastic alopecia seen in Bile duct carcinoma. Has been associated with crusting of the footpads and alopecia in cats.
- - variants of Lymphosarcoma, including:
- Hormonal disease (Feline endocrine alopecia syndrome)
- - Stud tail
- - Hypothyroidism - hair loss around flanks and tail base, but not usually itchy
- - Diabetic dermatosis
- - Cushings syndrome - can manifest as hyperpigmentation, alopecia, seborrhea, calcinosis cutis, and secondary pyoderma. In cats, the skin becomes extremely friable. In diabetes mellitus, pruritus and secondary infection rarely occur.
- - Thymoma
- - Pinnal alopecia - hairloss over ears - no therapy required