Quick answer
Benadryl may be safe to treat dog allergies and manage anxiety symptoms when given in appropriate doses. An incorrect dose of Benadryl could be extremely harmful, which is why you need to make sure you give a dose based on your dog’s weight. The rule of thumb is to administer 2-4 mg of Benadryl per kilogram of body weight.
Read on to learn more about the drug, how and why it can be used to treat dogs, its side effects, risk factors, and more.
What is Benadryl?
Benadryl is one of many brands of the antihistamine diphenhydramine. Antihistamines like this are used to relieve the symptoms of allergies, common colds, and more. Although it is made for humans, it is often recommended by DVMs to treat dogs as well. Some forms of Benadryl include:
- Benadryl for Children (Liquid Benadryl)
- Benadryl tablets
- Topical Benadryl
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Uses of Benadryl for Dogs
When it comes to dogs, vets will most likely recommend Benadryl if you have allergies. Other uses of Benadryl include managing anxiety symptoms (acting as a mild sedative) and even motion sickness when a dog travels.
Allergies
Benadryl is often used to treat a dog’s symptoms when it experiences an allergic reaction. The three types of allergies that dogs experience most are environmental allergies (also known as seasonal allergies), atopic dermatitis, and food allergies. Veterinarians may recommend Benadryl to treat mild allergy cases. However, severe allergic reactions require a visit to the veterinarian or animal hospital.
Some signs and symptoms of allergies in dogs include the following:
- Sneezing
- Urticaria
- Insect bites
- Rhinorrhea
- Eyes full of tears
- Itchy skin
- Skin irritation
- Difficult breathing
- Ear infections
- Hair loss
Anxiety
For dogs with anxiety, a vet might recommend Benadryl. However, it is important to note that the drug may not be successful in reducing your dog’s anxiety. While some dogs may experience some sedation or drowsiness under its effects, others may become even more anxious or hyperactive as it can increase their heart rate.
Some sources of anxiety for dogs include:
- Fireworks
- Travelling
- Temporal
- Sudden change of environment
Benadryl Dosage for Dogs
The dosage of Benadryl you can give your dog will depend on his weight. According to the antihistamine dosage chart in the Merck Veterinary Manual, the recommended dosage of diphenhydramine is 2 to 4 mg/kg, IM, PO, or SC, every 8 to 12 hours as needed. This means that pet parents should administer 2 to 4 milligrams (mg) per kilogram of body weight every eight to 12 hours orally or subcutaneously, as needed.
If you have difficulty calculating the correct dosage for your dog, it may be best to consult your veterinarian before administering the medication.
Risks of giving Benadryl to dogs
One of the main risks of giving the drug to dogs is an overdose of Benadryl. This can happen if the owner does not follow established weight guidelines and feeds more than his dog needs. Some dogs may even have an allergy to diphenhydramine.
Substances such as decongestants and alcohol are toxic to dogs. If the type of Benadryl you are giving contains either of them, it could seriously harm your dog. Owners should also be careful about how Benadryl interacts with other medications their dogs may be taking. Additionally, Benadryl should not be given if a dog has certain health conditions, such as glaucoma, cardiovascular disease, and others.
Common side effects of Benadryl include:
- Drowsiness
- Dry mouth
- Increased heart rate
- Hypersalivation
- Urinary retention
How Much Benadryl Can You Give to a Dog Frequently Asked Questions
Can Benadryl be harmful to dogs?
It depends on each dog. If your dog is allergic to diphenhydramine, its administration could have very negative effects on your dog’s health. Also, if you don’t give the right dosage, it could be harmful to your dog too.
What type of Benadryl can I give my dog?
You can give your dog any form of Benadryl that does not contain alcohol, decongestants, or any other ingredients toxic to dogs in its formula.
What is an alternative to Benadryl that I can give my dog?
Over-the-counter antihistamines such as Claritin (loratadine) and Zyrtec (cetirizine) can be used to treat allergy symptoms in place of Benadryl (diphenhydramine). However, you should first ask your vet to make sure they are safe for your particular dog.
Summary of Money’s guide on how much Benadryl you can give a dog
- Benadryl may be safe to treat dog allergies and manage anxiety symptoms when given in appropriate doses.
- An incorrect dose of Benadryl could be extremely harmful, which is why you need to make sure you give a dose based on your dog’s weight.
- The rule of thumb is to administer 2-4 mg of Benadryl per kilogram of body weight.
- Over-the-counter medications such as Zyrtec and Claritin can be used as alternatives to Benadryl, but owners should consult their veterinarians first to make sure they are safe.
- Owners should always consult a licensed veterinarian before administering any type of over-the-counter medication.