Do you feel like your dog or cat may have an ear infection? Did you know that they are usually from another underlying problem? Two of the most common reasons can be food or an environmental allergy. They can change the micro environment within the ear canal. This change in the environment allows yeast and bacteria to grow. Sometimes there is a discharge coming from the ear. The color of the discharge may help us determine what kind of organisms may be growing within the ear canal. The only reliable way to know what is breeding within the ear canal if to take a culture. Unless the underlying allergy or cause of the problem is identified and eliminated the problem may return. (Even if given a prescription ear medication). If the condition turns into a chronic condition, it can be very difficult to rectify.