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Safe Zyrtec Dosage for Dogs (2021)

Safe Zyrtec Dosage for Dogs (2021)

Cetirizine (generic name for Zyrtec) can be used for the short-term treatment of allergy symptoms in dogs. It’s available over-the-counter where you would typically buy human-grade antihistamine products.

Frustrated and worried about your dog’s excessive itching, hives, water eyes, and sneezing? Consider trying Zyrtec. It’s considered safe provided the dosage is correct. In addition, there are other important things to consider before administering Zyrtec to your dog that will be covered in this post.

Dog allergies can affect pets of all ages. Their symptoms range from mild to severe and depend largely on the allergen.

What is Zyrtec?

Zyrtec is a non-sedating antihistamine that is available over-the-counter. Originally, it required a prescription but the FDA made it available to the public in November 2007.

This is considered a 2nd generation antihistamine. The 1st generation antihistamines like Benadryl are more powerful but also more likely to result in drowsiness.

As a 2nd generation antihistamine, Zyrtec is considered an H1 blocker. This means the medication is less likely to cross the blood-brain barrier.

Is Zyrtec Safe for My Dog?

Veterinarians sometimes recommend Zyrtec (active ingredient cetirizine) for dogs with allergies.

The antihistamine properties in the drug work by blocking receptors on blood vessels, tissues, and lungs. Allergy symptoms flare when histamine is released through the body.

That intense itch that your dog has is caused by this excessive release of histamine. Zyrtec, however, blocks the histamine from binding to receptors. This is how allergies in dogs are managed with this medication.

Unlike Benadryl, this medication is less likely to make your pet drowsy. Additionally, it only requires one daily dose. Zyrtec is also prescribed to humans. Even children can use it. But is Zyrtec okay for dogs?

As it turns out, this popular drug might one of the safest pet antihistamines. That said, it’s important to understand that high doses of Zyrtec can cause serious cardiac events in dogs. In this case, more is not better.

Always follow the veterinarian’s guidelines for dosing your dog.

Avoid Zyrtec-D in Dogs

Zyrtec-D was specifically developed for human consumption and includes pseudoephedrine. The ingredient relieves congestion in humans but can cause serious complications in dogs.

Pseudoephedrine overstimulates the central nervous system and heart. It can cause canine seizures, heart failure, and death in some dogs.

WARNING: Do not use the Zyrtec-D formula for dogs. That particular medication includes pseudoephedrine which can cause toxicity in pets.

Zyrtec is considered safe for dogsPin

Why Use Zyrtec for Dogs?

Zyrtec has emerged as a safer, more effective alternative to Benadryl and other H1 antagonists.

This is a second-generation antihistamine that is also prescribed for humans. Like many drugs that were initially designed for human use, Zyrtec is considered safe for dogs/animals.

Second-Generation Antihistamine

Second generation antihistamines including Allegra (fexofenadine), Claritin (loratadine), and Zyrtec (cetirizine) were developed to reduce or eliminate the effects of sedation and adverse side-effects in people with allergies.

Like Benadryl, it relieves allergic reactions in pets, including watery eyes, sneezing, itching, and inflammation.

Itch Relief for Dogs

Allergies can cause similar reactions in dogs and people. If your dog has allergies, you may notice the following signs:

  • Irritated skin
  • excessive itching
  • water eyes
  • rubbing the face
  • biting at their legs or paws
  • skin infection
  • fur loss

A study published in The Canadian Veterinary Journal assessed the effects of Zyrtec on canine atopic dermatitis, the second most common cause of allergic skin disorders in dogs

As the researchers note, this condition affects up to one-third of our canine companions. Approximately 18 percent of the dogs treated with Zyrtec experienced relief from pruritus, the primary symptom of atopic dermatitis.

Safety Factors of Zyrtec in Dogs

Zyrtec is well tolerated in dogs and produced only mild side-effects. In some dogs, no side-effects have been reported.

Other pet antihistamines, including doxepin, cyproheptadine, and terfenadine, produced more frequent adverse reactions in clinical trials. Cetirizine, on the other hand, appears to be safe.

Single Dose Advantage

A major advantage of using Zyrtec for dogs is that it requires a single daily dose. Other antihistamine products require at least two or three doses per day to produce noticeable results.

What is the Correct Zyrtec Dosage for Dogs?

To find the correct Zyrtec dosage for dogs it’s important to get your dog’s current weight. Generally, the recommended dose for dogs is 1 mg/kg or 10–20 mg per dog, once or twice daily.

*source: Merck Veterinary Manual

Always follow your veterinarian’s advice above and beyond what you read here.

Remember: The dosing guidelines on the package are designed for people. Ask a veterinarian to suggest the standard dosage. The right dosage may depend on the dog’s size.

Are There Any Side Effects in Zyrtec for Dogs?

Most medications carry side effects. Zyrtec is no exception. Although this drug is safer than other antihistamines, it may still cause adverse reactions, including:

  • Excessive salivation
  • Urine retention
  • Nausea and vomiting
  • Constipation

Zyrtec is not recommended to dogs with liver or kidney problems as it may worsen their symptoms. Most side effects are rare.

What Causes Allergies in Dogs?

Several types of antihistamines for pets exist, and each has a different mechanism of action.

Choosing one depends largely on what caused an allergic reaction in the first place.

Like their human companions, animals can develop an inflammatory response to various foods and substances. Some are born with allergies, while others develop them later in life.

Allergies occur when the immune system overacts to foreign scents, food ingredients, and so on.

When your pet is exposed to allergens, his immune system begins to release histamine. This compound triggers inflammation, itching, edema, and other symptoms.

Common causes of allergies and/or inflammatory responses in dogs include:

  • Flea Bites
  • Grass
  • Pollen
  • Food sources
  • Environmental
  • Dust mites
  • Weeds
  • Bee sting

The same happens in humans, so we’re not that different from our furry friends from this perspective.

That’s why most antihistamines will work for both humans and pets, but at different dosages. When determining the best zyrtec dosage for dogs, consult with a veterinarian.

Dogs can develop different types of allergies, depending on the substance that triggers an immune reaction. These include allergic dermatitis, or skin allergies, food allergies, and acute allergic reactions.

Skin allergies, for instance, can be caused by fleabites, environmental allergens, or certain foods. If your dog is allergic to flea saliva, he may experience itchiness, skin redness, and swelling, among other symptoms. Itchy skin is also a symptom of food allergies and sensitivities.

Acute allergic reactions are by far the most dangerous. Some dogs may have severe reactions to vaccines, bee stings, or other allergens and enter anaphylactic shock. This life-threatening condition requires emergency care.

Zyrtec is safe for dogs with allergiesPin

When to Not Give Zyrtec to Your Dog

Zyrtec can cause urinary retention and should not be give to dogs with any kidney problems. It should also be avoided in dogs with medical conditions including:

  • Glaucoma
  • Seizure Disorders
  • Difficulty urinating
  • Older dogs
  • Working dogs
  • Pregnant dogs

Relieving a Dog’s Itch Naturally

Natural alternatives may work as a temporary solution while waiting to see the veterinarian.

Some of the methods mentioned below can help to reduce itch in dogs. They don’t, however, take care of the problem. The only way to relieve a dog’s allergies is to determine the exact cause and avoid it.

Oatmeal Bath

Oatmeal is more than a hearty breakfast choice, it can also help to ease the irritation and itch from allergies.

Parents have been using it forever to treat children with bug bites, chicken pox, and other skin irritations. It can also be used on dogs.

In order for oatmeal to work, it should be mixed into a paste and smoothed onto the skin. This can be done in the bath to avoid a mess.

You can also purchase shampoos for dogs that are made with pure oatmeal. A few excellent choices include:

Pet Silk Oatmeal Shampoo

Pet Silk Oatmeal Shampoo is designed to soothe dry, itchy skin while moisturizing your dog’s coat. It is made with oatmeal, silk, vitamins, and herbs. Made in the USA and biodegradable.

Epi-Soothe Oatmeal Cream Rinse

Epi-Soothe Cream Rinse contains oatmeal and is to be used after bathing. It is formulated to help relieve dry, itchy, sensitive skin. It also makes your pet’s coat more manageable, prevents tangles, and imparts a high sheen to the coat.

Perfect for cats, dogs, and horses.

Vetoquinol Care Aloe & Oatmeal Shampoo

Vetoquinol Care Aloe & Oatmeal Shampoo is specially formulated to soothe dry skin for both dogs and cats. Its formulation adds essential moisture while providing a deep rich lather that gently cleans without removing natural skin oils and leaves the coat with a pleasant coconut fragrance. Soap-free. Paraben-free. Silicone-free.

DermAllay Oatmeal Shampoo

DermAllay Oatmeal Shampoo is a soothing, soap-free, general purpose oatmeal shampoo which is indicated for coat and skin conditions. Works for itchy skin and acts as a moisturizer.

Other Alternative Options for a Dog’s Itchy Allergies

One of the best places to shop online for dog health care items is 1-800-PetMeds. They carry pretty much anything you could ever want and it only takes a quick search to find what you are looking for.

Some of the top items sold for dog allergy skin relief include:

Yucca Intensive Holistic Animal Care

Be Soothed. Tea Tree Oil Skin Relief

Be Soothed Shampoo

Hemp Allergy Aid Soft Chews

Licks Skin and Allergy

Allermyl Shampoo

How Do Pet Antihistamines Work?

Antihistamines are the first-line of treatment for allergies in both pets and humans. Older formulas caused drowsiness, memory problems, sleepiness, fatigue, and poor mental focus. The latest types of antihistamines are safer and more effective.

These medications come in tablet, cream, syrup, capsule, and spray form, so they’re easy to administer. In general, they’re recommended for short-term use.

The main types of antihistamines for pets are H1- and H2-antihistamines. The former bind to histamine H1 receptors in certain tissues and may help relieve allergic reactions affecting the respiratory tract.

These are usually prescribed for sneezing, itching, and runny nose.

H2-antihistamines work by binding to histamine H2 receptors in the digestive tract. These medicines may help treat acid, reflux, stomach ulcers, and other gastrointestinal conditions.

The first types of antihistamines are the ones prescribed for allergies. By acting on the H1-receptors, they help reduce inflammatory responses and provide relief from allergic reactions. Both Zyrtec and Benadryl are classified as H1 antagonists.

Safe for Mild to Moderate Allergies in Dogs

Not too long ago, vets prescribed Benadryl for dogs and other animal companions. Although it’s effective, it may cause sleepiness and drowsiness. These side effects are due to diphenhydramine, its primary compound.

This medication isn’t approved for veterinary use by the FDA. However, when using the correct Zyrtec dosage for dogs, it’s generally safe for most pets with mild-to-moderate allergies.

It is effective at relieving hives, itching, sneezing, redness, swelling, and other allergic reactions.

This dog could use a safe Zyrtec dosage for dogs to stop that itch.Pin
dog sitting and scratching itself on the grass

Keep Your Dog Allergy-Free

Although over the counter medication is easy to purchase and use, it’s imperative that you seek veterinarian advice before administering.

Allergies can be just as devastating for pets as they are for their human companions.

Don’t make any compromises when it comes to the health of your beloved friend. Consider using Zyrtec for dogs to keep him allergy-free and prevent complications.

Always consult a veterinarian before giving pills or supplements to your pet.

Some dogs are hypersensitive to Zyrtec and other antihistamines, so don’t take unnecessary risks. Also, beware that this medication can interact with other drugs or worsen existing conditions.

If your furry friend is vomiting, he may have an allergic reaction or something more serious. Some medications can help. Check out our guide to giving your dog Pepto-Bismol for vomiting!

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The Canadian Veterinary Journal 2004 May 1; 414-417

Scott DW, Miller WH Jr, Griffin CE. Muller & Kirk’s Small Animal Dermatology VI. Philadelphia: WB Saunders, 2001:543–666.

Merck Veterinary Manual

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