If your pet has any of the suspect food allergy symptoms including:
watery eyes
runny nose/sneezing
itching
rash red skin
diarrhea
vomiting
loose stool
constipation
It is critical to determine if your pet's allergies are actually coming from the foods you are feeding which can be a daily irritation causing them these sufferable conditions.
You may be able to determine your pets food allergy by partaking in a carefully planned food trial, however that is a time lengthy process and while it works well to identify protein allergies your pet may have however, a food trial is very hard to determine what allergies to plant materials your pet may be experiencing.
In this case, it is best to do food allergy testing to determine the cause of your pets allergies. It is important to know that most conventional veterinary offices do not offer food sensitivity testing, but only testing for true food allergies which is a completely different circumstance and different set of symptoms learn more here.
Thankfully, there is now a great easy at home test kit that only requires a sample of your pet's saliva to determine the cause of their food sensitivities. The test looks at the top 24 most common protein and plant source food allergens in both cats and dogs. The testing kit then gets mailed in and your results will return in about 3 weeks and include which foods your pet tested positive allergic to, and some alternatives to feed your pet to stay clear of those particular allergens.