can dogs take allegra. Overview of Fexofenadine for and Felines
Fexofenadine, often known by brand names such as Allegra® or Telfast®, is a second-generation antihistamine that can be used for dogs and cats to manage itching and other symptoms associated with allergies. Unlike some other antihistamines, fexofenadine is generally less likely to cause drowsiness.
**Important Warning:** When using Allegra® for pets, make sure to choose the product containing only fexofenadine as the active ingredient. Avoid any product that combines fexofenadine with pseudoephedrine, like Allegra-D®, as pseudoephedrine can be toxic to animals. Additionally, the liquid version of human fexofenadine often contains xylitol, which is harmful to dogs.
Fexofenadine’s use in pets is not extensively studied; much of what is known comes from research on its effects in humans and information about other antihistamines used in veterinary medicine. Histamine is a chemical involved in allergic responses, and it affects the body through two types of receptors: H1 and H2. H1 receptors are linked to symptoms like itching and swelling by causing blood vessels to expand and fluid to leak into tissues. H2 receptors, on the other hand, influence heart rate and stomach acid production.
Antihistamines, like fexofenadine, work by blocking histamine’s action, specifically targeting the H1 receptors to reduce symptoms like swelling and itchiness without affecting heart rate or stomach acid levels. While fexofenadine can be bought over the counter, it should only be used in pets under the guidance of a veterinarian, as it is not FDA-approved for animal use but can be prescribed legally as an extra-label medication.
Brand Names and Other Names
This drug is approved solely for use in humans. Available human formulations include Allegra®, Telfast®, and several generic versions. Currently, there are no specific veterinary formulations of this drug.
Uses of Fexofenadine
Fexofenadine is mainly used to treat allergic conditions such as atopic dermatitis and allergic rhinitis. For pets, it can help manage itching, especially when administered consistently and started before the itching becomes severe. Antihistamines tend to be most effective when used regularly and before the pet is exposed to allergens.
Precautions and Side Effects
Fexofenadine is generally safe and effective when prescribed by a veterinarian, but it can cause side effects in some animals. It should not be used in pets with known allergies or hypersensitivity to the drug. Additionally, it is not approved for use in pregnant or nursing dogs or cats and should be used cautiously in animals with kidney disease.
Fexofenadine can interact with other medications, so it’s important to consult your veterinarian to check for potential drug interactions. Medications that may interact include antacids, erythromycin, ketoconazole, and ivermectin. Common side effects include sedation, lethargy, dry mouth, vomiting, and possible diarrhea.
How Fexofenadine Is Supplied
Fexofenadine comes in several forms: tablets, oral dispersible tablets, and oral suspension. The tablet sizes are 60 mg and 180 mg, while the oral dispersible tablet is available in a 30 mg dose. However, the dispersible tablet is designed to dissolve on the tongue, which makes it challenging to administer to pets. Additionally, some dispersible tablets may contain xylitol, which is toxic to dogs.
The oral suspension of fexofenadine is available in a 30 mg/5 mL concentration (6 mg/mL), but it also contains xylitol, making it unsuitable for use in dogs. There are also combination products like Allegra-D® that include pseudoephedrine; these should not be used in pets. Human oral suspensions with xylitol are not recommended for animals due to their potential toxicity. Always consult with your veterinarian before administering any medication.
Dosing Information
Never administer medication to your pet without first consulting your veterinarian. If cost is a concern, consider exploring how pet insurance might help.
For dogs, fexofenadine is typically dosed at 1 to 2.5 mg per pound of body weight (2 to 5 mg/kg) every 12 to 24 hours. Some studies suggest that higher dosages, such as 9 mg per pound once daily, may also be effective. Due to tablet sizes, dosages are often rounded to the nearest tablet size, with small dogs receiving about 15 mg and large dogs about 30 mg.
Fexofenadine has not been extensively studied in cats, and no standard dosages are established. Reports suggest a total dose of 10 to 15 mg per cat orally once daily.
You can administer fexofenadine with or without food; if your pet experiences gastrointestinal upset, giving it with food might help. The length of treatment varies depending on the condition being treated, how your pet responds, and any side effects. A minimum trial of two weeks is often recommended to assess the effectiveness of the medication. Always complete the full course of treatment as directed by your vet to prevent a relapse, even if your pet seems to improve.
