The Side Effects of Thunder Shirts for Dogs

If Fido makes for your lap when a storm looms on the horizon, a thunder shirt may help him calm down.
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Thunder shirts are snug-fitting wraparound shirts designed to help your dog deal with his anxiety during thunderstorms, fireworks or other stressful situations. The shirts work along the same lines as swaddling an infant, touching pressure points that help your dog slow his breathing and enter a more relaxed state of mind. While you don't have the same type of side effects to worry about as you would with anti-anxiety medications, thunder shirts are not without potential danger.

High Anxiety

Dog Whisperer Cesar Milan cautions against waiting until your dog is at a high level of anxiety before putting on the thunder shirt. The dog may associate the shirt with the high level of anxiety he is in when you put it on him and develop anxiety about the shirt itself. He suggests initially using the shirt when your dog is in a calm, relaxed state of mind so your dog makes the association between calmness and the shirt and putting it on before the storm or other stressful event to prevent anxiety from peaking.

Summer Hot Dog

Summer thunderstorms often come with sweltering heat and high humidity that make dogs pant and drool. While a thunder shirt's fabric contains 55 percent cotton and considered a breathable material, the remaining content is synthetic fiber that could hold in enough body heat to contribute to your dog overheating during extreme weather. A thunder shirt's design slows your dog's breathing to put him in a calm state, so if your dog is panting heavily and rapidly in the shirt, he may be overheating.

Hairy Houdini

Thunder shirts come in seven sizes, so make sure it is the proper size for your dog. A too-small shirt may pinch, and one that is too large causes friction that is annoying to your dog. While most dogs calm down with the proper use of a thunder shirt, those that do not like feeling restricted or feel irritated by an ill-fitting garment may try to wriggle free. Don't leave your dog unsupervised when he is wearing the shirt as he may become entangled trying to escape, resulting in injury or suffocation.

Canine the Destroyer

Remove hair from the hook-and-loop closures with a wire slicker brush each time your dog wears the thunder shirt. Hair buildup makes the closures less secure, increasing the possibility of your dog chewing on annoying, flapping closures. If your dog feels uncomfortable in the shirt, he may bite at the lower portion of the shirt. If swallowed, pieces of the cotton-polyester-spandex material could potentially cause intestinal blockage. Keep an eye on your dog while he is wearing the shirt and contact your veterinarian if you feel he might have ingested some of the shirt's material.