Antihistamines for canine allergies

Antihistamines for canine allergies

Health & Safety

If your dog is prone to allergies that make them generally uncomfortable, producing symptoms such as dry, itchy skin, runny eyes and other forms of discomfort, you will need to work with your vet to establish what it is that your dog may be allergic to, and the best way to go about sorting things out.

Finding the root cause of the allergenic trigger can often mean that you can stop or limit your dog’s exposure to it, solving the problem, but this is not always possible in every case. Canine allergies can be complex, and a huge range of innocuous things can potentially trigger allergies, meaning that it is not always possible to find out what the trigger is for your own dog. Added to this, even if you can identify the trigger, it is not always possible to keep your dog from being exposed to it, for instance if one of their triggers is to something like pollen or grass.

One of the most commonly used medications to help with the management of canine allergies are antihistamines, which can help to reduce skin irritation, inflammation, hayfever-like symptoms and other presentations of the allergy. In this article, we will look at how antihistamines work in more detail, and why they can, in some cases, help to keep your dog with allergies more comfortable. Read on to learn more.

How do antihistamines work?

If your dog is allergic to something, exposure to their particular trigger will generate an allergic reaction in their body, which leads to the body producing a chemical compound called histamines in order to combat what the body sees as an attack on itself. Histamines bind with other cells in the body, such as those in the skin, and around the nose, mouth and eyes, which is why these areas of the body are generally the areas most affected by allergenic symptoms.

This all comes about due to the body viewing the trigger itself as an invasive threat to the body, when it is not actually an issue in practice, and all of the unpleasant symptoms of allergies are generated by the body’s histamine response to their trigger, rather than something inherent in the substance causing the allergy itself.

Antihistamines work by blocking the body’s histamines from binding with the cells in the body to produce an allergic reaction, stopping the body from generating allergy symptoms as a result of this.

Using antihistamines for your dog

You have probably seen antihistamines of various types on sale over the counter at your local pharmacy, or on the shelf in larger supermarkets. However, despite the fact that they are easy to buy and don’t need a prescription for people, antihistamines are actually fairly powerful medications that have a systemic effect on the body of the dog, and so should not be viewed as a cure-all or obvious solution to allergies in dogs in every case.

Antihistamines can produce a range of side effects in dogs treated with them, and in some cases, can cause sensitivities as a reaction to the medication themselves. For these reasons, antihistamines for your dog must only be bought after consultation with your vet, and with a veterinary prescription for the correct type and dosage for your dog.

Diagnosing allergies that may benefit from antihistamines

If your dog has itchy skin and sore, runny eyes and other similar symptoms, it may seem like the obvious conclusion to make is that they are allergic to something. However, you must get your vet to confirm this for sure, as a range of other conditions and diseases can also generate symptoms like these, but will need to be managed differently.

Your vet may take skin scrapings, blood samples and run other diagnostic tests, as well as potentially running exposure testing on your dog to get to the bottom of what is causing their allergy to flare up in the first place.

Once your vet has confirmed a diagnosis of allergy in your dog, they will then discuss the various different options available to you to treat or manage the condition, and antihistamines are one of the most common solutions.

There are a reasonably wide range of different types of antihistamines available for dogs, some of which have different active ingredients and dosage levels, and your vet will work out which one is likely to prove to be the best fit for your dog.

Correctly dosing antihistamines is determined by things like the weight and condition of your dog, and the response that they show once treatment with the medication has begun.

Generally, a dog with allergies will begin to show an improvement within a week of beginning on antihistamines, and if you do not see any improvement, it is time to go back to the vet. Antihistamines do not tend to produce many side effects in the dog when used correctly, although some dogs may appear more tired and lethargic than usual during the first few days of treatment. If you have any questions and concerns about allergies, antihistamines and your dog, speak to your vet for more information.

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