Dog allergies are a relatively common health problem, which often prove incredibly frustrating to treat.
Although food allergies often get the bulk of the attention, many dogs are also allergic to things in their environment, such as pollen, dander or dust (in fact, these types of allergies are much more common than the infamous food allergies).
Allegra is often very helpful for treating these types of environmental allergies, and it may put an end to your dog’s itching.
Allegra is the brand name for a drug called fexofenadine. A type of antihistamine, Allegra is licensed for human use in the treatment of seasonal allergies (hay fever) and skin itching (particularly when the cause of the itching is unknown). It doesn’t cure allergies; it simply treats the symptoms allergies usually cause.
One of the selling points of Allegra is that it is a relatively new drug, called a second-generation antihistamine. Unlike Benadryl and most other first-generation antihistamines, Allegra doesn’t pass through the blood-brain barrier very well, which means that it doesn’t cause the drowsiness that is characteristic of first-generation antihistamines.
When your dog’s body (or your body, for that matter) is exposed to a pathogen, it releases a chemical called histamine. This also occurs when a dog has allergies, except that in the case of allergies, the immune response is excessive and directed at a normally benign substance.
Among other things, histamine helps white blood cells and some types of protein to penetrate the body’s capillaries, where they can fight off the infection or foreign invaders. However, histamine also causes inflammation and itchiness. This is why your eyes water or your dog’s skin itches when exposed to an allergic trigger.
Interestingly, the reason that humans often suffer from runny noses, watering eyes and sneezing fits is because the cells that contain histamine in our bodies (called mast cells) are primarily located in the upper respiratory system. By contrast, most mast cells in dogs are found in the skin, which causes them to itch when exposed to an allergic trigger.
Antihistamines, as their name implies, block the actions of histamine, thereby preventing the inflammation and itchiness. There are a variety of different antihistamines — Benadryl (diphenhydramine) is the most familiar example — and each works in a slightly different way.
Sometimes, a given antihistamine can provide more relief than others, depending on the allergen and the afflicted individual. This is why you and your vet may need to experiment with several different medications before finding one that provides relief for your pup.
Environmental allergies (which are also called seasonal allergies in some cases) can present in a number of different ways. Some of the most common signs and symptoms they cause include:
Despite the number of different ways environmental allergies can present, itchiness (particularly when it is focused around the paws) is likely the most common sign of environmental allergies. However, itchiness can also indicate a number of other problems, so you’ll need to consult your vet to obtain a positive diagnosis.
If your vet suspects environmental allergies are the problem, he or she will likely prescribe Allegra or some other antihistamine to help reduce the symptoms and improve your dog’s quality of life. Be sure to take it exactly as prescribed, and follow your vet’s instructions carefully to ensure the best outcome for your dog.
Allegra is usually administered at a rate of 1 to 2.5 milligrams per pound of body weight every 24 hours. However, precise dosing is not always possible or required.
Allegra usually comes in 60-milligram tablets, and it is thought to have a large margin of safety, so vets often recommend the following dosing regimen:
Some vets recommend splitting the daily dose and giving it twice per day, while others recommend taking it all at once.
In either case, you should always follow your veterinarian’s instructions when administering Allegra or any other drug – even if it contradicts the dosing schedule detailed above.
While Allegra is generally considered a pretty safe drug for dogs, it is important that you only obtain the basic formulation of the drug. Do not give your dog Allegra D or other versions that contain decongestants, such as pseudoephedrine, as these medications can be very harmful to dogs.
Similarly, you should avoid oral suspension forms of the medication, as these often contain xylitol, which can be very dangerous for your pet.
Allegra may cause problems for dogs who are pregnant or lactating, as well as those who have kidney issues, so it is generally not prescribed in such cases. In high doses, Allegra may also alter heart function, so pets with cardiac problems may not be ideally suited for the drug.
Additionally, dogs who are fed a large amount of fruit or fruit juice (perhaps in the form of frozen treats) may not be able to absorb Allegra properly.
The side effects of Allegra in dogs aren’t well established, but they are likely similar to those experienced by humans. These include:
If you suspect that your dog is suffering from any of these conditions, contact your vet immediately and follow the instructions provided.
It is important to note that Allegra and other antihistamines aren’t the only way to treat dog allergies, and they aren’t always effective. You may need to try some other strategies for reducing your dog’s allergy symptoms to help your pup feel her best.
Some of the best strategies for mitigating the symptoms of environmental allergies include:
Does your dog battle environmental allergies? What medications or treatments have proven helpful in your case? Has your vet recommended Allegra? Has it caused your dog to have any side effects, or has it worked without causing any problems?
Tell us all about your experiences in the comments below!
Ben is a lifelong environmental educator who writes about animals, trees, outdoor recreation, science and environmental issues. He lives with his beautiful wife and spoiled-rotten Rottweiler in Atlanta, Georgia. Read more by Ben at FootstepsInTheForest.com or @FootstepsForest on Twitter.
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