Fexofenadine is also available an oral suspension that contains xylitol (NOTE: Xylitol may be toxic in dogs). The human oral suspension is not recommended for use in pets.
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.
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.
When a dog consumes antihistamines, depending on the amount ingested, toxicity can occur. Poisoning due to antihistamine overdose is caused by: The constriction of the smooth muscles in the respiratory tract. The increased permeability of the capillaries.
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.
The most commonly used antihistamines for dogs include: Diphenhydramine (Benadryl®) Loratadine (Claritin®) Cetirizine (Zyrtec® or Reactine®)
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.
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.
Toxicity to pets
When accidentally ingested by dogs and cats, antihistamine poisoning can result in clinical signs of severe agitation, lethargy, sedation, aggression, abnormal heart rate, abnormal blood pressure, vomiting, diarrhea, inappetance, seizures, respiratory depression, and even death.
Quercetin, also known as "nature's benadryl," is a natural antihistamine found in many fruits and vegetables that can help ease your pup's allergy symptoms.
Research has shown that quercetin can turn off histamine production and control inflammation. So it's often known as Nature's Benadryl. Quercetin also helps manage cellular activity associated with inflammation … meaning less itching!
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.
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.
Diphenhydramine (Benadryl): 1mg per pound (one 25mg tablet for a 25lb dog) twice daily. Cetirizine (Zyrtec) ¼ - ½ mg per pound (one 10mg tab per 30-40 lbs) twice daily. Loratadine (Claritin): ¼ mg per pound (half of a 10mg tablet per 20 lbs) once daily.
Telfast® 120mg is indicated for the relief of symptoms of seasonal allergic rhinitis in adults and children over 12 years of age. Telfast® 180mg is indicated for the relief of itching that occurs with hives in adults and children over 12 years of age.
Some of the best oral antihistamines for dog allergies include Curist Allergy Relief (levocetirizine), fexofenadine (brand Allegra), and cetirizine (brand Zyrtec), which can help reduce your sneezing and itching.
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.
The dosing schedule is also much more convenient, with dogs weighing over 10 lbs getting a single 10mg tablet once daily. Dogs weighing less than 10 lbs can have half of a 10mg tablet once daily. Chlortrimeton is another excellent antihistamine for dogs, and is the drug of choice for kitty allergies as well.
Benadryl is safe to give your dog for allergies, anxiety, motion sickness, and vaccine side effects. Though a typical Benadryl pill is 25 mg, you should only give your dog 0.9-1.8 mg per pound of weight. Make sure that the Benadryl you're giving your dog only contains diphenhydramine.
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.
Many people experience allergies from pets, and it may be difficult to avoid potential allergens that cause symptoms. Over-the-counter medications like antihistamines and decongestants can help quickly relieve symptom from cats and dogs. Nasal corticosteroids may take longer to kick in.
The human form of loratadine is the same as the form administered to dogs and it can be purchased at any drug store or grocery store. The usual dose of loratadine for dogs to relieve allergies is 0.12 mg/lb to 0.22 mg/lb (0.25 to 0.5 mg/kg).