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Determine if your dog has allergies. Try putting your dog on a diet trial. Challenge your dog's diet. Restrict your dog's activity. Follow up with your veterinarian. Prevent ear infections.

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Allergies are often the primary source of inflammation in the ear, which makes the ears more susceptible to infections. While it may be difficult to determine an allergic cause, it helps to start paying attention to factors such as if new foods or treats were introduced before the ear infection flared up. If they contained a particular protein, you may want to avoid that giving your dog that protein. Animal proteins and dairy products in food are more likely to cause allergies for pets than grains are, despite the popularity of the notion that grain free diets are better for dogs with food allergies. Specifically, put your dog on a diet trial with a novel, or new, protein, one your dog has never eaten before. New prescription diets should be fed exclusively for at least 8 weeks and ideally for a minimum of 12 weeks. Give no treats, table scraps or other food sources during this time. This may help to determine if food proteins are the problem and home in on which are culprits. The best novel protein diets are prescription formulas because they will have the least likely chance of cross-contamination with other protein sources, but they are often the most expensive choice. At the end of the trial, if your dog is not showing signs of ear inflammation or skin allergies (most commonly itchy paws and sometimes itching of other areas of the body), then you can 'challenge' your dog's diet with a single type of treat or the old food. If you notice signs of irritation near the ears, feet, or skin when you re-introduce the old food or treat, then you know that this food or any food containing this protein should be eliminated. If the ear infections tend to spring up at the same time of year every year, a seasonal environmental allergy may be causing the ear infections. While your dog has an ear infection, you should make sure he doesn't get excess moisture in his ears. Avoid letting your dog play in water, swim, bathe, or be groomed until the ear infection has cleared up. Extra moisture will aggravate the ear infection and make it last longer. Keep checking in with the veterinarian until the ear infection is completely gone. Some ear infections are mild and easily treated in 1-2 weeks with topical medications and cleaning. Some infections are more complicated and may take many weeks, further testing, treatments or procedures to treat. Follow your veterinarian's recommendations about when to check in, since the vet can help you determine if the ear infection is cleared or if more needs to be done. Once your dog has had an ear infection, he's more likely to struggle with them throughout his life. The good news is that there are several things you can do to prevent ear infections in your dog. Here are several preventative measures:  avoid letting your dog swim or bathe too frequently plug your dog's ears with cotton before bathing him flush your dog's ears with a product containing salicylic acid (which helps wet ear canals dry) check and treat any allergies your dog may have frequently clean your dog's ears