The best hypoallergenic diet includes proteins and carbohydrates that your cat has never had before, since most food allergies develop from exposure to certain ingredients. Hypoallergenic cat foods make use of uncommon sources of protein that are not usually incorporated into cat food. Many hypoallergenic cat foods contain rabbit, duck, lamb or venison, as a source of protein, since most cat food formulas contain chicken, beef, eggs or fish.
In many cases, it's very difficult to figure out the specific cause of your cat's food allergy. You may have to try several different formulas until you find one that works for your cat. In addition to this, many food allergies manifest as skin problems in your cat, not necessarily including gastrointestinal symptoms (such as diarrhea). This causes the mis-treatment of the condition, as this is also a symptom of sarcoptic mange, seasonal skin irritation, and other skin-related conditions. Many people will not immediately suspect food allergies to be the cause of their cat's skin problem.
