Loratadine (Claritin): ¼ mg per pound (half of a 10mg tablet per 20 lbs) once daily. Clemastine (Tavist-1, Antihist-1): 0.02mg per pound (one 1.34mg tablet per 65lb dog) twice daily. Diphenhydramine (Benadryl): 1mg per pound (one 25mg tablet for a 25lb dog) twice daily.
Antihistamines with the active ingredients of diphenhydramine, chlorpheniramine, cetirizine, clemastine or loratadine are usually safe for most healthy adult dogs. Hydroxyzine is another dog-safe antihistamine and one of the most effective available, but it's only available on prescription.
Antihistamines. Diphenhydramine (Benadryl®), cetirizine (Zyrtec®), and loratadine (Claritin®) are commonly used antihistamines that relieve allergy symptoms or counteract allergic reactions. Antihistamines are usually safe but can make some dogs drowsy and others hyperactive.
According to the Merck Veterinary Manual, the standard dose for Benadryl® is 2–4 milligrams per kilogram of body weight, or 0.9–1.8 milligrams (mg) of Benadryl® per pound. Therefore, a simple and practical dose is 1 mg of Benadryl® per pound of your dog's weight, given two to three times a day.
Overview of Fexofenadine for Canines and Felines. 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. Fexofenadine is considered less sedating than other antihistamines.
Telfast®- (active ingredient fexofenadine ) these are available in 60 to 180 mg tabs. But note that while not likely to overdose, the dosage for most dogs is only 5-10 mg / Kg once or twice a day.
OVER-THE-COUNTER ALLERGY DRUGS
You can use over-the-counter antihistamines for your dog's allergies. They can be really quite helpful in some dogs, but they're really unlikely to control an acute or severe flare up.
Zyrtec is one of the safer medications you can give to your dog, so as long as you do so correctly and under your vet's guidance, your pet should be good to go. Zyrtec is also a difficult medication for a dog to overdose on. They have an extremely high tolerance for it, so long as they aren't allergic to it.
It is recommended to give your dog 0.5mg per pound of body weight. You can safely give Zyrtec to your dog up to 20 mg per day. It should only be administered orally.
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.
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.
If an antihistamine has an additional active ingredient, like pseudoephedrine, your pet may experience severe hyperactivity, hallucinations and even seizures. Because it does not take much of this ingredient to become detrimental, exposures can be life-threatening.
There is no clear evidence that any one antihistamine works better than another, so other factors can be considered when choosing an allergy medication.
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.
Consult with your veterinarian to determine if other drugs your pet is receiving could interact with cetirizine. Such drugs include central nervous system depressants. The most common adverse effects of cetirizine are sedation, lethargy, vomiting, drooling (hypersalivation), and lack of appetite.
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. Learn more about ZYRTEC®.
Over-the-counter antihistamines, such as diphenhydramine (Benadryl®) and cetirizine (Zyrtec®) relieve allergy symptoms in both humans and dogs. Because certain antihistamines (e.g., Benadryl) can cause drowsiness, they are sometimes used to help calm dogs with anxiety.
Other safe antihistamines for dogs include Claritin (loratadine) and Zyrtec (cetirizine). They produce less sedation than Benadryl does but could still make your dog drowsy. Warning: Make sure your OTC allergy medicine only contains antihistamines.
Paracetamol is a very popular painkiller in humans, however it can be toxic or fatal in small animals. Dogs are less sensitive to paracetamol than cats. A 20kg dog would need to ingest over seven 500mg tablets in order to suffer toxic effects.
Telfast tablets are available in three different strengths, each with its own indications: Telfast 60mg strength: Seasonal hayfever and year-round allergic rhinitis. Telfast 120mg strength: Seasonal hayfever allergies. Telfast 180mg strength: Seasonal hayfever allergies and itchy skin rash/hives.