Giving Dogs Benadryl for Allergies or Stress?

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Benadryl, also known as diphenhydramine, is an antihistamine often used to help both dogs and humans mitigate allergy symptoms and help them sleep. While many veterinarians believe that Benadryl is safe for dogs, it is also essential to consult your vet before giving your dog any product, especially if your dog is taking other types of medicine. Dogs and humans react differently to most medicines, though, so it is important not to assume your dog will respond to Benadryl the same way you do.  Broadly, Benadryl is considered safe for your dog, but there are underlying conditions that may make it inadvisable, including low blood pressure, pregnancy, or cardiovascular issues.

How does Benadryl work? 

Very basically, it blocks histamines from the receptors in your body, relieving allergy symptoms. In dogs,  Benadryl is most commonly used to help with allergic reactions such as itching and hives but can also help limit sneezing, red eyes, and a runny nose.  

Benadryl can be highly effective in mitigating issues with environmental allergies. Still, if your dog is struggling with breathing,  Benadryl will not be as effective, and you should seek immediate advice from your veterinarian. If you decide to give your dog Benadryl make sure to keep an eye on them to see if they have an adverse reaction to the medicine. 

One other common reason that your veterinarian may recommend Benadryl is for stress, nerves, or motion sickness. If your dog is scared of loud noises, the car, or is just generally nervous; it is reasonable that you may want to use Benadryl to sedate them. Temporary or occasional use is recommended, so there may be other more beneficial remedies to your dog that might calm rather than sedate. 

Side Effects

Some dogs actually have an opposite reaction to Benadryl and become more hyperactive rather than sedated. Other side effects include dry mouth, increased heartbeat, issues with urination, and even rapid breathing. Some signs that you gave your dog too much include tremors, constipation, being overly agitated, increased heartbeat, and dilated pupils. If you think you may have given them too much, reach out to your veterinarian or veterinary emergency clinic immediately. Finally, some dogs, just like some humans, may be allergic to Benadryl, so if you are giving your dog Benadryl for the first time, make sure that you keep an eye on them to see if they are negatively reacting. 

Time-Release Capsules

One important thing to note is that you should never use time-release capsules with dogs because dogs absorb medication differently than humans do. Time-releasing capsules could give your dog too much at one time and cause an adverse reaction. Some liquid Benadryls contain alcohol, so make sure that if you choose a liquid version, you choose a non-alcoholic, children’s version as a safer option. 

Allergies are so unpleasant for your dog, and it can be hard to see them suffering. Benadryl can be a great option when used correctly. 

The ElleVet Team
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