Read This Before Giving Your Dog Allegra For Allergies!

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Does your dog have bad allergies? Are they itchy with runny eyes and/or sneezing?

You want to know if Allegra can help so let’s get straight to the point:

Can I Give My Dog Allegra?

Vets do prescribe Allegra, but one version is off limits to pets. Allegra-D contains pseudoephedrine which can easily harm your dog.

The regular over-the-counter formula is not toxic at low doses.

Dogs Can Take Allegra (with vet approval)

Never use a leftover supply!

Though this 2nd generation antihistamine reduces histamine effects in animals, it’s important to avoid putting your dog at risk.

A Vet’s View Regarding Allegra

We asked for Sara Redding Ochoa’s (DVM) input and here is what she told us…

“Allegra can help dogs with allergies. It can be given once a day and often has the same effect as Benadryl (which really needs to be given 3 times daily).

Allegra is typically for mild allergies, whereas more severe allergies may require Apoquel.”

Results of an Excellent Study

Fexofenadine was administered to 15 dogs with atopic dermatitis. The Slovenian researchers gave an amount on average that was 7.5 times the human recommended dose (or approximately 36mg per pound of each dog’s body weight).

Observed side effects were minimal and included “eye and nasal discharge, loss of appetite
and skin rash.”

Overall the treatment was successful.

In fact, it was concluded that Fexofenadine was, “effective in reducing the severity of pruritus and the presence of skin lesions in dogs with atopic dermatitis.”

This study, entitled The Efficacy of Antihistamine Fexofenadine Versus Methylprednisolone in the Treatment of Atopic Dermatitis In Dogs, is worth reading for additional information.

Confirm Correct Treatment

This drug (Fexofenadine or Fexofenadina) must be given for the right reasons and at the prescribed dose.

Allegra can block the mechanisms that trigger your dog’s allergies, but go about it responsibly.

Get a proper diagnosis!

What’s actually causing the underlying allergy should be determined. Allegra may not be the best treatment for your dog’s condition.

How to Address Allergies

Stubborn allergies often originate from the environment, food as well as various other external factors. Yet, it can be very difficult to pin down the exact problem.

Again, a thorough check-up will identify not only what the dog is allergic to but also optimal treatment options.

Only after an assessment of the situation would a good veterinarian prescribe an antihistamine (such as Allegra, Benadryl or even Claritin).

Causes And Symptoms

Typical allergen triggers include:

  • Dander
  • Mold spores
  • Dust
  • Feathers
  • Cigarette smoke
  • Food ingredients
  • Harmful prescription drugs

Allergy-prone dogs can be affected in many different ways. Reactions can surface as red/itchy skin, watery eyes, increased scratching, sneezing, vomiting, diarrhea and constant licking.

2 Serious Side Effects

Although Allegra tends to have relatively few downsides compared to other antihistamines, coughing and/or vomiting could occur (thankfully rare) and would be concerning.

Stop use immediately and contact your vet if your dog experiences those two symptoms.


FYI: Mild stomachache and dizziness are common side effects besides those documented in the above-mentioned study.


Make Some Key Changes

Do an evaluation of your home before quickly reaching for Allegra.

If need be, clean the house. Sweep and mop the floors as well as vacuum the rugs and furniture.

Pet dander can turn up everywhere! Eliminating it, as best you can, may actually cure your dog’s allergies (something Allegra cannot do).

Effective Home Remedies

Does your dog suffer from skin irritations that manifest in the form of itching and scratching?

You can mix baking soda in water and pour it on the itchy parts.

Another approach is to bathe your buddy in oatmeal that’s been dissolved in cool water for about ten minutes. It often works!

The Bottom Line

Allegra also works on dogs, but the D version is super dangerous!

Really the ultimate source(s) ie. allergens should be pinpointed and eliminated to truly handle pesky allergies. Quite often a vet’s assistance is needed.

Going it alone, with any type of OTC Allegra, is a bit risky for the average dog.

Get your furry friend checked out! Otherwise, stick to safer remedies.

What Do You Think? Have Your Say Below…

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35 thoughts on “Read This Before Giving Your Dog Allegra For Allergies!”

  1. I have a 2 year old dog with bad allergies. He’s constantly scratching and bites both his tail and paws. He bites his tail until it bleeds.

    A vet prescribed Apoquel, but it’s gotten more expensive. I’ve also tried apple cider vinegar for the itching but it doesn’t work. No luck with Benadryl either. Oatmeal baths only relive it for a while.

    I feel so bad for him. He’s not active when he gets these allergies. He doesn’t eat or drink enough. It’s sad. I need to try something else. I’m hoping Allegra will work. I just started giving it to him today. I’m splitting a 180 mg pill in half. Wish us luck!

  2. I have a Bichon. He’s all white and has the tear stains. I have tried everything. Many other Bichon owners avoid corn in their food and buy bottled water. I’ve changed his food accordingly and also bought a filter for my tap water. Yet he still has those tear stains.

    I clean them with wipes but they drain within 2 hours, then more tear stains. I read that Clear Eyes is loaded with antibiotics which isn’t good. I would love to clear this up. Now I’m trying a small does of Allegra. Does anyone have another idea?

    1. Marlo’s tear stains, without any other problems, are a result of dogs like yours and mine (Japanese Chin) having eyes that bulge out. They must tear all the time to keep their eyes wet to keep them clean and free of infection and disease. While it is possible that your dog has allergies, clearing them up will not stop the tear stains.

      Heaven forbid you find something that stops your dog from tearing. Dogs with dry eyes have the same issues humans with dry eyes have. They are extremely injury and infection prone without all that tearing. It could blind the dog.

      A typical Bichon show dog will have to live with constant bleach and peroxide treatments around their eyes. Bottom line is part of having a Bichon is having to accept that you’ll likely have a dog that has tear stains, which are harmless by themselves.

  3. My vet gave me this info:

    Zyrtec – 5mg once daily @ approx 30 lb
    Claritin – 5 mg once daily @ approx 30 lb
    Benadryl – 25mg tab 1.5 tab twice daily @ 30 lb
    Omega 3’s (fish oil) – 600mg EPA/DHA total daily

    1. Thank You! The expensive scripts from our vet caused too many side effects. She never suggested human OTC drugs for him.

      1. Hi Maggie. Colleen has provided a very nice bit of information relative to dosing of specific OTC drugs. However, the information does not specifically provide dosing on a per pound of body weight basis.

        From my own experience with dogs, it’s critical to understand that dogs metabolize drugs very differently than humans. As an example, last year my dog was prescribed a dose of 25mg of Atarax three times a day. The human dose is usually 10mg.

        Consistently, throughout the posts, you will note that many of us with dogs have done well with the dose of 180mg. You will find reports of doses people have used with smaller dogs. Someone made a suggestion of using the children’s preparation.

        If your dog is small, perhaps starting with the children’s dose would suffice. You can always increase the dosage gradually.

    2. What’s the dosage for Allegra for a 65 pound dog?

  4. What are the dosage levels for small, medium and large dogs by weight? Our dog is 8 pounds.

  5. Your experience confirms what so many of us have found with using Allegra. Certainly it works better than all the meds prescribed by vets for the problems described. Thanks for the affirmation.

  6. Many years ago I had a Cocker Spaniel that had severe allergies. We tried everything, changing her food, steroids and childrens’ Benadryl per the recommendations of our vet. The Benadryl worked better but not great. I had to give it to her several times a day which never went well.

    She struggled with me every time. She was not good at taking the pill and hiding it in peanut butter never worked, she was always suspicious of what I was giving her.

    That said, we had a human prescription for Allegra. I was desperate and split the pill in half to give her (the dog weighed approximately 30 pounds). She was always scratching at her ears and toes and tummy, licking till they were red. I basically thought to myself, this is ether going to help her or kill her but either way she will be better off. Luckily it helped her, dramatically.

    The itching and scratching and licking stopped. Her ears became fine and her skin cleared right up. An added bonus was I only had to fight with her once a day to take a pill and if I missed a day it didn’t seem to wear off right away. She has since passed away, but it worked well for her when she was with us.

    It didn’t have any adverse effects, and I would say that they are able to metabolize it pretty well from her experience. Made her existence so much better. She was always crying and whimpering as she scratched at her ears, otherwise without it, and I felt so sorry for her.

    1. I found that giving a small amount of peanut butter is a very helpful way to give a dog a pill. The first time that I went to give my Lab a pill, he gave me a deep growl. So knowing that his treats are made of peanut butter, I got a spoon and put some on it with the pill. That was several years ago and I’ve been doing it ever since. This has made our life easier.

      1. My dog rejects peanut butter unless it is on something. I have gotten good at hiding pills in various things. Cheese or ham is his favorite. I started using the children’s chewable tabs, often breaking them in half as they can be large. This way they don’t get a nasty taste if they bite the pill itself. It’s also harder for him to spit out. The ones that dissolve quickly are the best.

      2. I use just a dab of peanut butter on a dog biscuit. Just enough to hold the pill on and down it goes.

      3. I have 4 dogs and have found that by keeping the peanut butter in the fridge it makes it stiffer. This not only holds the pill better, but makes it easier and less messy. The girls all love their chilled peanut butter treat!

  7. I’m a bit worried about Piriton, half per day due to drowsiness. I’m considering Allegra.

  8. I have been reading up on Colostrum (from a cow) and it seems that animals have reacted very well to it, it helps alleviate allergies. Has anyone tried this before? Thanks

    1. Hi Sandra. All female mammals produce colostrum around the time of birthing, and that includes humans. The production of colostrum does not continue, but rather is the first milk that is produced.

      It’s true that antibodies are passed through breast milk (which is why mothers are encouraged to breast feed,) but in all probability they are species/breed specific. So it doesn’t seem logical that cow’s colostrum would benefit a dog. I have never seen it commercially available.

      You may think of it this way: for humans with allergies, allergy shots are often recommended. The person is first tested for specific allergies, and then a shot is prepared from the specific antigen.

      Over time an immunity is built up to the offending allergen (antigen). Building up an immunity to a specific antigen results in the production of specific antibody – often referred to as the lock-key relationship.

      1. Actually colostrum is available in powdered form, usually in a capsule. My vet prescribed it for my dog when she was very ill and on 5 different meds. It helped her feel better, though
        I’m not certain how it did so.

        There is commercially available cow and goat colostrum. It may or may not help with allergies, but it does seem to help with some conditions. It seemed to improve my dog’s immune system.

  9. I have a 9-pound Yorkie with terrible allergies. She is constantly licking paws, watery eyes and scratching (has even broken skin inside her ears). She doesn’t have mites or fleas (allergies only as determined by our vet). She was on prescription meds, Apoquel, until the vet ended up out of stock. Zyrtec doesn’t really help. Can you tell me what dosage I can give her of children’s’ Allegra? I have 30mg chewables.

    1. Wanda, the way drugs are metabolized by dogs is quite different than humans. I once was prescribed 10mg of Atarax. Subsequently, my dog was prescribed 25mg of Atarax, several times a day. After getting multiple bug bites on my legs, I took one of the dog’s 25mg of Atarax and was in la-la land for over a day.

      My point is that it’s hard for lay people to know the correct dose for an animal with a drug appropriate for both. I would look on the package and see if there is any dosing instructions for administering Allegra to children by weight. In your case, the thing that concerns me is both the size and breed of your dog. I would be very clear about potential side effects of the drug. As you will see by reading previous posts, several of us have found that the full adult dose works for a 75 lb dog.

      As a lay person I would never recommend a dose for your pup, but if you wish to try the Allegra purchase a pill splitter. Try splitting the pill into 4 parts. You may consider trying the smallest dose to see if there’s any effect. In human care, the dose can then be raised until there is a favorable response with no side effects.

      In truth, I have no idea what would work for such a small pup, but you may consider partial dosing with increases as needed. Since Allegra is not presently prescribed for dogs, there is no way to call someone and get the correct answer, Good luck!

      1. Maybe look into the type of Allegra made for children. Surely they make such a thing.

        1. There are certain types of Allegra that will seriously harm your dog such as Allegra-D as well as the one designed for kids. Research or ask your vet and find out about side affects. I, myself, am going to find Colostrum or Quercetin. Holistic remedies are my chosen route.

  10. Hi everyone. I’m reading up on effective treatments for my dog’s allergies. He’s been on steroids so many times, and I hate to keep him on them. I’m at the end of a 3-month prescription-only diet. It has helped, but I’m realizing that environmental allergens still trigger his discomfort.

    It makes me so sad that he doesn’t play and isn’t happy. I’ve tried Benadryl to no avail. I’m going to try 60mg per day of Allegra. I like what I’m seeing you all say about the results. Wish me luck!

  11. My vet told me I could use Chlor-Tripolon for dog allergies as well. My German Shepherd scratches a lot and rubs her eyes; hoping the Chlor-Tripolon helps.

    1. I did an internet search of the drug you identified, and discovered that the drug is also referred to as Chlorpheniramine and subsequently learned that it is also called Chlor-Trimeton (an over-the-counter antihistamine).

      As a nurse I can tell you this is an older antihistamine and may be considered a first generation drug. I cannot attest to the “better” effectiveness of Chlor-Trimeton vs. Allegra. However, if you read through some of the other comments you will see that others including myself, have tried a plethora of prescription drugs but seem to have found success with Allegra.

      Two things to bear in mind 1.) while animals may be treated with human medications, the drugs may not have the same effect, and the doses administered may be quite different than what is ordered for humans. 2.) Animal allergies present quite differently than in humans. In addition to scratching and biting, paw licking is very common even to the point of dogs developing lick granulomas.

      If the drug your vet has prescribed seems to not work, you know from this site that others have used many antihistamines but have found that the Allegra does work. Good luck! I know how difficult it is to watch your pet suffer with allergies.

  12. In my own experience, Benadryl did nothing for my dog. She had actually chewed a wound into her hind quarter, and as she walked she would bring up her hind legs as though to scratch.

    I called the vet and got her some Atarax, an otherwise very effective antihistamine, but like the Benadryl, it did nothing to relieve her symptoms. After reading as much as I could about the Allegra for dogs, I tried the 180mg tab for my 75 pound Airedale. She has been symptom free since.

    1. My dog started on Cyclosporine, a generic and cheaper version of Atarax, and it worked great for about 2 years. Now it has no effect. I tried Benadryl with no results and I’m looking for the info you provided. Here’s hoping my boy can get some relief.

      1. Hi Brent. Cyclosporine is a chemotherapy. I absolutely cannot imagine why your dog would have been given that and clearly Atarax is not a generic for cyclosporine, again a chemotherapy. Atarax is a powerful antihistamine, but it may not work for your dog. The Allegra seems to work best, and I use the 180mg for a 75 pound dog. Give it a try.

  13. My Labrador has been constantly dealing with allergies and leaks his paws. We have tried Benadryl but it makes him drowsy. I was thinking of switching to Allegra which comes in 180mg tablets since I take it myself. Can you recommend the right dose for his weight? He is 76 pounds.

  14. My vet did ok giving my dog 2.5mg of Zyrtec, but I was looking to switch to a pediatric dose of Allegra due to inclusion of a decongestant. My dog has congestive heart failure due to cardiomyopathy and I’m just trying to get her some relief from the symptoms, generally unrelated to allergies, but similar symptoms.

    1. Please do not confuse congestive heart failure as having anything to do with allergies, or a condition that would be relieved by a decongestant. Congestive heart failure requires Digoxin to make the heart beat more effectively, and Lasix to pull off extra fluid stressing the heart. A antihistamine such as Allegra or Benadryl will work for itching, scratching, compulsively licking the paws.

      If your dog is not having these symptoms, it doesn’t need an antihistamine and certainly not a decongestant. Remember that the products with the “D” for which you have to sign, relieve sinus congestion in people. Truly, the symptoms may seem the same, but clinically they are very different.

      Also, keep in mind how small your dog is. Given that her heart is enlarged, you don’t want to do anything that would stress the liver or the kidneys. Please speak with your vet so that you have a better understanding of the interplay of the organs most especially in a dog the size of yours.

  15. My Cocker Spaniel weighs 33 pounds and I’m giving her 80mg daily. I chose Allegra because is the only one that works except for cortisone. I am considering an increase in the dose to 120mg daily. What do you think about it?

    1. Breno, in my opinion, 80mg should be working if your dog is 33 pounds. Do you not see any results at this dosage? Do you notice anything different at all? I would be very careful about increasing that Allegra dose but I am not a vet.

  16. Thank you for the answer. Is there a way to know the correct dosage to give a dog? My dog is 24 pounds and I have the 10mg Allegra tablets.

    1. Hi Angie. Your dog is small so start out with a low dose. A 10mg tablet would be the max I’d use. Try to see if you notice a difference with just one.

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