The most common side effects of antihistamines in dogs include sedation and drowsiness. This is more commonly noticed with first-generation antihistamines such as diphenhydramine (Benadryl®). Newer generation antihistamines such as cetirizine (Zyrtec® or Reactine®) have less of a sedating effect.
Additionally, while dogs react to antihistamines differently, Zyrtec has had a higher response rate than others. The drug has minimal side effects, although some pets do become drowsy. The dosing schedule is also much more suitable, with dogs weighing over 10 lbs getting a single 10mg tablet once daily.
While Benadryl is not yet FDA-approved for veterinary use, it is considered safe for use in dogs and cats and is commonly used in veterinary practices across the U.S.
The active ingredient in Zyrtec is cetirizine. Cetirizine is an antihistamine commonly used to treat itchy skin in dogs. It's a popular prescription for canines because most dogs tolerate the medication very well, and it doesn't have the effect of leaving your pet sedated and lethargic.
You can safely give Zyrtec to your dog up to 20 mg per day.
You can see a quick overview of dosages here: 5 Ibs: 2.5 mg or ½ of a 5 mg tablet. 10 Ibs: 5 mg or 5 mg tablet. 20 Ibs: 10 mg, one 10 mg tablet, or two 5 mg tablets.
Here's the recommended Zyrtec dosage for dogs based on their weight: Less than 10 pounds: 2.5 milligrams (half of a 5-milligram pill or a quarter of a 10-milligram pill) 10–50 pounds: One 10-milligram tablet. 50+ pounds: Up to two 10-milligram tablets.
Benadryl may be contraindicated with certain health conditions. It should be used with caution in dogs who have seizures in dogs, heart disease in dogs, or high blood pressure (i.e. hypertension in dogs).
Yes. Benadryl is an over-the-counter medication that is labeled for humans but is generally considered safe for dogs in the appropriate dosage. Always consult with your veterinarian before giving your dog any medication.
Claritin and Zyrtec are safe treatments to give to a dog to help control mild allergy symptoms. These medications will help with very mild signs while more severe allergies may require prescription allergy medication from your veterinarian.
Antihistamines are commonly used to treat dog allergies. Their histamine-blocking quality tackles airborne allergens and reduces symptoms in your pup. The safest over-the-counter options for your dog include Benadryl, Zyrtec, Claritin, and Allegra.
Coconut Oil
It also can reduce allergic reactions. You can apply coconut oil directly to your dog's coat, dry, cracked pads, cuts and sores. Dym likes to add a little coconut oil to food. Add coconut oil slowly to your pet's diet, about a quarter teaspoon per every 10 pounds of body weight.
Benadryl should never be combined with any other medications! Benadryl is a first-generation allergy medication. This means that it is more likely to cause side effects, such as drowsiness and drooling. Dry eyes and mouth are other possible side effects.
Benadryl is also used to treat insomnia, motion sickness, and mild cases of Parkinsonism. A main difference between Benadryl and Zyrtec is that Zyrtec tends to cause less drowsiness and sedation than Benadryl. Both Benadryl and Zyrtec are available in generic form and over-the-counter (OTC).
Antihistamines can be of significant benefit in controlling skin allergies in dogs. Although not as universally effective as cortisone type medications (prednisone), they have fewer side effects and significantly help up to half of dogs with skin allergies.
According to the Merck Veterinary Manual, the safe dosage is 2-4 milligrams of medication per kilogram of weight, or 0.9 to 1.8 milligrams per pound. This amount can be administered two to three times daily, depending on your dog's symptoms.
If your dog experiences seasonal allergies, your vet may recommend administering Benadryl on a regular basis. Some dogs may even take Benadryl once daily as a long-term therapy to mild allergies. Usually, these dogs receive Benadryl or diphenhydramine once daily.
It is possible that Benadryl can help your dog calm down. One of the most common side effects of Benadryl is sedation. You may notice that your dog gets a bit drowsy after taking Benadryl. If you believe your dog needs help sleeping, you must talk to your veterinarian first.
It will usually take 30 minutes for Benadryl to take full effect, and you want your pup calm and anxious-free. In terms of what form of Benadryl, that's entirely up to your vet. It doesn't really matter if you use the brand name medication or not.
Consult with your veterinarian to determine if other drugs your pet is receiving could interact with cetirizine. Such drugs include central nervous system depressants. The most common adverse effects of cetirizine are sedation, lethargy, vomiting, drooling (hypersalivation), and lack of appetite.
Response and effectiveness. Peak concentrations are reached within one hour of administration of Zyrtec tablets or syrup. The onset of effect occurs within 20 minutes in 50% of people and within an hour in 95%. Effects persist for at least 24 hours following a single dose of Zyrtec.
Allergies in dogs are different than allergies in people. Histamines cause upper respiratory allergies in people, whereas cytokines (not histamines) cause itchy skin in dogs. For dogs with underlying allergies, antihistamines don't control the cytokines (signaling proteins) that cause inflammation and itch.
Cetirizine (Zyrtec® or Reactine®) is one of the most commonly used over-the-counter antihistamines recommended by veterinarians. Claritin® can be used but is not typically recommended by veterinarians as some forms of Claritin® contain decongestants such as pseudoephedrine which is very toxic to dogs.