Cetirizine (Zyrtec® or Reactine®) is one of the most commonly used over-the-counter antihistamines recommended by veterinarians. Claritin® can be used but is not typically recommended by veterinarians as some forms of Claritin® contain decongestants such as pseudoephedrine which is very toxic to dogs.
Claritin and Zyrtec are safe treatments to give to a dog to help control mild allergy symptoms. These medications will help with very mild signs while more severe allergies may require prescription allergy medication from your veterinarian.
Best treatment: Antihistamines
Antihistamines are commonly used to treat dog allergies. Their histamine-blocking quality tackles airborne allergens and reduces symptoms in your pup. The safest over-the-counter options for your dog include Benadryl, Zyrtec, Claritin, and Allegra.
Clemastine Fumarate. Also recommended as an antihistamine for dogs is clemastine fumarate. It is one of the most effective antihistamines for dogs with itchy skin.
You can safely give Zyrtec to your dog up to 20 mg per day.
Cetirizine (Zyrtec®, Reactine®) is an antihistamine used to treat and prevent pruritus (itching) associated with atopic dermatitis, urticaria (hives), and insect bite reactions in cats and dogs. Its use is in cats and dogs is 'off-label'. Many drugs are commonly prescribed for off-label use in veterinary medicine.
Here's the recommended Zyrtec dosage for dogs based on their weight: Less than 10 pounds: 2.5 milligrams (half of a 5-milligram pill or a quarter of a 10-milligram pill) 10–50 pounds: One 10-milligram tablet. 50+ pounds: Up to two 10-milligram tablets.
Fexofenadine, commonly known as Allegra® or Telfast®, is a second generation antihistamine drug that may be used for dogs and cats to control itching and other signs related to allergic conditions.
Claritin is used to treat symptoms like runny noses and hives in humans, but it is primarily used to address itchy skin in dogs. It is not, however, appropriate for emergency use, such as during a life-threatening allergic reaction.
Pet allergy relief
When you can't live without your pet, a medicine for dog and cat allergies can help control your pet allergy symptoms. ZYRTEC® starts working at hour 1 and stays strong day after day, so you can reduce your cat and dog allergy symptoms.
Vets generally prescribe Claritin for dogs in a dosage 0.2 milligrams per pound of body weight. This can translate as giving a small dog around 5 milligrams of Claritin every day, or 10 milligrams for a larger dog.
Apoquel starts relieving allergic dog itch and inflammation due to skin allergies within 4 hours — and controls it within 24 hours.
Zyrtec is active for up to 24 hours, so your dog will be free from a runny nose, itchy skin, sneezing, and other symptoms for the whole day. Also, Zyrtec is safer and has fewer side effects than other allergy medicine, which makes it the best remedy for your dog during the spring season.
Dosing Information of Cetirizine for Dogs and Cats
Cetirizine is dosed in dogs at 0.5 mg per pound (1 mg/kg) orally once to twice daily.
If your pet has been exposed to any type of antihistamine or toxic substance, contact your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 immediately.
Cetirizine (Zyrtec) ¼ - ½ mg per pound (one 10mg tab per 30-40 lbs) twice daily.
Many people use antihistamines to treat allergy symptoms. Zyrtec (cetirizine) and Claritin (loratidine) are two popular brands. They contain different compounds but appear to be equally effective. Antihistamines can reduce allergy symptoms, such as watering eyes, itchy skin, hives, and swelling.
All ZYRTEC® medicines start working at hour 1 on the first day you take it.
Veterinarians use diphenhydramine, commonly known by the brand name Benadryl, for dogs on a regular basis to treat allergies, travel anxiety, and motion sickness.
Antihistamines are usually safe but can make some dogs drowsy and others hyperactive. OTC antihistamine preparations may contain other ingredients such as decongestants that are not safe for dogs. Read the label carefully to ensure that the product only contains antihistamine.
Zyrtec is a popular second-generation antihistamine first prescribed to people. However, more and more veterinarians have started prescribing it to dogs in pain with pruritus caused by allergic dermatitis. The reason for this is Zyrtec is rather low-risk, however, it's not as effective as the drug Apoquel.