If your dog has experienced an allergic reaction in the past or suffers from allergies, you may have wondered whether there are any over-the-counter medications that could help. While many over-the-counter human medications are unsafe for your dog, several antihistamines such as claritin, benadryl and zyrtec are safe to give your dog at the right dose under veterinary supervision.
Before giving your dog any medication, it’s vital to know when it is appropriate to give it, potential side effects, and the correct dose. It may surprise you to know that human and dog doses differ, and even some “safe” medications can be dangerous if your pet has a certain condition or is taking other medications.
As a pet owner, it’s so hard watching your fur baby scratching non-stop because of allergies. I’ve been there, frantically googling “can you give Claritin to dogs” at 2 AM while my pup couldn’t stop itching. The short answer is yes, but there’s so much more you need to know before reaching for that medicine cabinet.
The Quick Answer: Yes, But Be Careful
Loratadine (Claritin) can indeed be given to dogs, but ONLY under specific circumstances and with proper dosing. This isn’t something you should just decide to do without proper information.
Claritin is generally well-tolerated in dogs experiencing itching, allergies, and allergic reactions to insect bites, but it can cause vomiting, hypersalivation (drooling), and sedation in some dogs. Always consult your vet before giving any human medications to your pet!
When Antihistamines Like Claritin Can Help Your Dog
Antihistamines work by blocking histamine receptors in the body which helps reduce allergic symptoms. According to veterinary research they can be beneficial for dogs with
- Seasonal allergies
- Environmental allergies
- Allergic reactions (like bee stings)
- Type-1 hypersensitivity reactions causing facial swelling and hives
- Motion sickness (though other medications might work better)
It’s worth noting that antihistamines seem most effective when used for acute allergy flare-ups or when started at the beginning of allergy season. If your doggo has been suffering for weeks already these medications might not help as much.
Effectiveness of Antihistamines in Dogs
Let’s be honest here – antihistamines aren’t miracle workers for all dogs, Studies suggest they only help control itching in approximately 1/4 to 1/3 of dogs with skin allergies This is because the allergic response in dogs isn’t completely related to histamines like it is in humans
While we humans get runny noses and watery eyes from allergies, dogs typically show redness and itchiness of their skin as their main symptoms. This difference in how allergies manifest means antihistamines might not be as effective for our four-legged friends.
Claritin Dosage for Dogs
If your vet gives you the green light to try Claritin, here’s the typical dosage recommendation:
Loratadine (Claritin): ¼ mg per pound of body weight once daily
(That’s about half of a 10mg tablet for a 20 lb dog)
This is significantly different from human dosing, so never just give your dog the same amount you would take yourself!
Important Warning About Claritin Formulations
⚠️ CRITICAL SAFETY WARNING ⚠️
Not all Claritin products are safe for dogs. Some forms of Claritin contain decongestants like pseudoephedrine (often labeled as Claritin-D), which is EXTREMELY TOXIC to dogs. Always check the ingredient list and only use plain Claritin (loratadine only).
Additionally, some liquid or rapid-dissolving forms may contain xylitol, an artificial sweetener that is highly toxic to dogs. Always read labels carefully before giving any medication to your pet.
Other Antihistamine Options for Dogs
If Claritin doesn’t seem to help your pup, there are other antihistamines that might work better. In fact, vets often recommend trying different antihistamines since one may work significantly better than another for your specific dog.
Here are some common alternatives with their typical dosages:
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Cetirizine (Zyrtec): ¼ – ½ mg per pound (one 10mg tab per 30-40 lbs) twice daily. This is one of the most commonly recommended over-the-counter antihistamines by vets.
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Diphenhydramine (Benadryl): 1mg per pound (one 25mg tablet for a 25lb dog) twice daily. May cause sedation, which could actually be helpful at night for itchy dogs who can’t sleep.
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Chlorpheniramine (Chlortrimeton): Common veterinary antihistamine.
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Hydroxyzine (Vistaril): 1mg per pound twice daily. This requires a prescription.
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Clemastine (Tavist): 0.02mg per pound twice daily.
Each antihistamine should be given for a 2-3 week trial before determining if it’s effective for your dog. Don’t give up after just a few days!
Combining Antihistamines with Other Medications
Antihistamines can be safely combined with many other medications for treating allergies in dogs. However, you should NEVER give multiple different antihistamines at the same time.
Some common combinations:
- Antihistamines + Omega-3 fatty acids (can enhance effectiveness)
- Antihistamines + Apoquel or Atopica (no known interactions)
- Antihistamines + corticosteroids like prednisone (can help reduce the overall steroid dose needed)
Some medications like Temaril-P or Vanectyl-P already combine prednisone with an antihistamine in one pill.
Boosting Effectiveness with Omega-3 Fatty Acids
High-dose omega-3 fish oil supplements can significantly enhance the effectiveness of antihistamines and help reduce skin inflammation. When used together, they provide better relief than either treatment alone.
Recommended dosages of combined EPA and DHA (the active omega-3s):
- Dogs under 30 lbs: 75mg PER POUND daily
- Dogs 31-60 lbs: 60mg PER POUND daily
- Dogs over 60 lbs: 50mg PER POUND daily
Start with a lower dose and gradually increase over about 2 weeks to allow your dog’s digestive system to adjust. High-potency products like Welactin are often recommended for their purity and concentration.
Potential Side Effects of Antihistamines in Dogs
Most antihistamines are fairly safe, but they can cause side effects in some dogs:
- Sedation and drowsiness (more common with older “first-generation” antihistamines like Benadryl)
- Paradoxical excitement (especially at higher doses)
- Loss of appetite
- Nausea or vomiting
- Constipation or diarrhea
- Dry mouth
Newer generation antihistamines like Claritin and Zyrtec typically cause less sedation, which is why many vets prefer them for daytime use.
When NOT to Use Antihistamines for Dogs
Antihistamines should be avoided or used with extreme caution in dogs with:
- Known sensitivities to antihistamines
- Respiratory diseases like asthma
- Liver disease
- Seizure disorders
- Working dogs whose performance might be affected by sedation
Higher doses of antihistamines (especially Benadryl above 5mg/kg) can have toxic effects including seizures, respiratory depression, and cardiovascular problems.
When to See a Vet Instead of Trying Antihistamines
While antihistamines can be helpful for mild allergies, they’re not always enough. You should definitely see your vet if:
- Your dog’s itching is severe and causing distress
- There are open sores or hot spots on the skin
- You notice unusual lumps, bumps, or swelling
- Your dog has ear infections along with skin problems
- The itching has been going on for more than a few days
- Your dog is having trouble breathing or seems uncomfortable
For more severe itching and inflammation, your vet will likely need to perform an examination to look for underlying causes (like fleas, mites, or infections) and may prescribe stronger medications like Apoquel, Cytopoint, or possibly prednisone.
My Personal Experience
When my retriever started scratching like crazy during spring pollen season, our vet recommended trying Zyrtec first, but it didn’t seem to help much. We switched to Claritin, and while it wasn’t a miracle cure, it definitely took the edge off his itching. Adding in fish oil supplements made an even bigger difference.
The key was being patient – it took almost two weeks before we really noticed improvement. That’s why the 2-3 week trial period vets recommend is so important!
Final Thoughts: Is Claritin Right for Your Dog?
Claritin can be a safe and effective option for some dogs with mild to moderate allergies. Its advantages include:
- Once-daily dosing (unlike some other antihistamines)
- Less sedation than older antihistamines
- Generally well-tolerated
- Inexpensive and readily available
However, it’s not right for every dog or every situation. More severe allergies often require prescription medications, and some dogs simply don’t respond well to antihistamines.
Always consult with your veterinarian before starting any medication regimen for your dog. They can help determine if Claritin is appropriate, recommend the correct dosage, and suggest alternatives if needed.
Remember that the best allergy treatment often involves a combination approach – addressing the underlying cause when possible, using medications to control symptoms, and making environmental changes to reduce allergen exposure.
Have you tried Claritin or other antihistamines for your dog? We’d love to hear about your experiences in the comments!
Uses of Claritin For Dogs
Claritin can be administered to dogs to treat the following conditions:
The three most common allergies in dogs are food, environmental and flea allergies. Itching, inflammation, and redness are common symptoms. Claritin can possibly help with skin irritation caused by allergies.
Did you know the most common food allergens for dogs are animal-products, namely chicken, beef and dairy. Learn about our Clean Protein Dog Food that is free from the top dog food allergens.
Insects bites or stings can cause your pet to have an allergic reaction. If the reaction is mild, such as swelling, itching, or hives, you can consider giving Claritin to reduce these symptoms under the direction of a veterinarian. If your pet has any facial swelling or difficulty breathing, seek veterinary care immediately.
Dogs suffering from cancerous mast cell tumors are likely to develop frequent chronic inflammation due to excessive blood histamine levels. Your vet may recommend an antihistamine such as Claritin to help provide relief, but keep in mind it will not treat the tumor. Speak with your vet before giving Claritin to your dog, especially if they have a tumor and/or are receiving other medications.
Vaccines are very important for preventing disease in your pup, and as a vet, I always recommend staying up to date with vaccines. As with humans, some dogs can experience a vaccine reaction, which is basically an allergic reaction to a vaccine, and these reactions can range from mild to severe. Your vet may recommend an antihistamine such as Claritin prior to vaccine administration, although Benadryl is usually chosen. Even though these allergic reactions can be scary, they shouldn’t deter you from administering vaccines to your dog.
Is Claritin Safe for All Dogs?
While Claritin for dogs is commonly prescribed for allergy relief, it can be fatal for pets suffering from certain conditions or currently on other drugs. Loratadine formulations shouldn’t be given to:
- Young puppies
- Nursing and pregnant females
- Dogs ailing from liver, kidney, and keratoconjunctivitis sicca disease
- Loratadine sensitive or allergic dogs
- Dogs on other contraindicated drugs such as cimetidine antacid, erythromycin antibiotics, or ketoconazole antifungal drugs
Vet Guide | What You Should Know About Over-the-Counter Antihistamine Use in Dogs and Cats
FAQ
How much Claritin do I give my dog?
Loratadine (Claritin): ¼ mg per pound (half of a 10mg tablet per 20 lbs) once daily.
Is Claritin or Benadryl better for dogs?
The best over-the-counter antihistamine for dogs has been Benadryl or diphenhydramine, although recently veterinarians have begun using Claritin (loratidine) and Zyrtec (cetirizine) in dogs. In cats, chlorpheniramine seems to work the best. This is given at 2 mg, which is a half tablet, twice a day.
Can dogs take Zyrtec or Claritin?
Can I give my dog claritin or zyrtec for allergy relief? If so, what No, I would not advise using either of these drugs. Histamine reactions are a very small part of the dog’s allergy problems, so these antihistamines will not help, unless there is an acute reaction like a bee sting, fireants, or a vaccine reaction.
Is 10 mg of loratadine safe for dogs?
Claritin (loratadine) is an antihistamine that can be used in dogs. It has a very wide margin of safety for them. The recommended dosage for dogs is 5–10 mg once or twice daily, or 5 mg per 25 pounds of body weight once or twice daily.