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Diphenhydramine Side Effects In Dogs

Diphenhydramine Side Effects In Dogs

We all feel the need to help our dogs when they are in a state of pain and discomfort. However, if your not a veterinarian, you should be giving out medications to your dog. While they might be helping you, they could do more harm than good to your furry companion. That’s why it’s so important to always consult a professional. However, that doesn’t mean that all human medications can’t be used on dogs. The dosage just has to be appropriate. Your vet will know best which to give the green light. Veterinarians often use diphenhydramine. It’s also commonly known as Benadryl. It helps with allergies, anxiety, motion sickness. However, it can also be a possible danger. To learn more about diphenhydramine side effects for dogs, keep on reading!

Diphenhydramine — What is it?

Diphenhydramine, or also known as Benadryl, is an antihistaminic. It falls under the first generation which basically means that it can cross the blood-brain barrier. That makes it very effective, but also very likely to cause side effects. The FDA still has to approve it for veterinary use, but it is widely considered to be safe for dogs and cars. It’s commonly used by many veterinarians.

It works by blocking the receptors that recieve histamine in the body. This gives a relief from symptoms of allergies such as: itchiness, sneezing, hives.

What is diphenhydramine used for?

Diphenhydramine is a great medication for treating mild to moderate symptoms of allergies. Either seasonal, environmental or food allergies. It can even help with insect or snake bites.

It helps with symptoms such as:

  1. Coughing
  2. Sneezing
  3. Hives
  4. Redness
  5. Runny nose
  6. Anaphylactic reactions

Vets also prescribe diphenhydramine for dogs with mast cell tumors to help with the effects of histamine release that these tumors cause. It can even help with heartworm disease.

Diphenhydramine side effects for dogs

As much as diphenhydramine helps with some conditions and symptoms of allergies, it’s still associated with a lot of side effects. That’s why it’s so important to always discuss it with your vet before giving this medication to your dog. The right dosage will keep the possibility of side effects lower.

Most side effects will occur within the first hour after the exposure. So make sure to keep an eye on your dog during that time. Monitor him carefully and make sure to notice any possible changes in his behavior.

If your dog develops any of the following symptoms after taking diphenhydramine, contact your vet immediately:

Common side effects associated with using Benadryl for dogs include:

  1. Diarrhea
  2. Vomiting
  3. Increased or decreased appetite
  4. Drowsiness
  5. Dry mouth
  6. Excessive drooling
  7. Increased heart rate

The side effects are more likely to occur in dogs with certain health conditions. So if your dog has any other medical issues, always let your vet know. Diphenhydramine side effects are essential common in dogs with conditions such as:

  1. Seizure disorders
  2. Hypertension
  3. Allergic lung disease
  4. Pregnancy
  5. Glaucoma
  6. Cardiovascular disease
  7. Hypothyroidism

Diphenhydramine overdose

However, symptoms can also occur if your dog had too much of this medication. It is possible to overdose, and therefore it is crucial to follow your vet’s guidelines when giving diphenhydramine to your dog.

Symptoms of diphenhydramine overdose include symptoms such as:

  1. Agitation
  2. Constipation
  3. Seizures
  4. Rapid heartbeat
  5. Dilated pupils

If your suspicious that your dog may had too much of this medication, be on the lookout for these symptoms. It you notice any of them, take him to the veterinary hospital right away. They will most likely induce vomiting to help your dog get the medication out of his system. However, some dogs can also develop allergic reactions to diphenhydramine. If you notice any symptoms of an allergic reaction, contact your vet immediately.

Dosage of diphenhydramine for dogs

Your veterinarian will be the one deciding on the right dosage for your dog. The following advice cannot replace any possible guidelines that you received from your vet. However, to get a rough idea about the dosage, keep on reading.

The Merck Veterinary Manual recommends administering 2-4 milligrams of diphenhydramine per kilogram of body weight, two to three times a day. However, this can largely vary amongst dog breeds.

It’s also important to never give this medication to puppies, as they are more sensitive than adult dogs. It’s also not recommended for pregnant bitches or bitches that are nursing.