My cat has 2 symmetrical stripes of hair loss and darkened skin from the base of his tail to about halfway up his back. My vet said it was probably allergies but we switched his food and nothing happened. I read about Cortisone Excess today and thought that might be the problem. Any suggestions?
This is called feline Alopecia. Yoou can read about it here:http://www.thepetprofessor.com/articles/article.aspx?id=352
Sometimes it is caused by allergies to the grains that are used as fillers in many commercial cat foods. It can also be a result of stress. It is not likely to be an excess of cortisone but can be hormonal if your cat is diabetic or has hyperthyroid.
Look into changing his food to one with no grains and if he is stressed try a natural product like composure liquid at www.onlynaturalpetstore.com or rescue remedy or feliway available at most pet supplies.
Please let me know if you have any more questions. I will be happy to help in any way possible.