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A. Highly overdosed loratadine can be dangerous. You should ring your vet without delay. It may not be too late to induce vomiting and/or give activated charcoal.

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Some of the most common antihistamines available include diphenhydramine, cetirizine, loratadine and fexofenadine. In general, and in smaller doses of these drugs, your pet may become tired, quiet, develop an upset stomach and may be a little unsteady on their feet.
Official answer. Yes, you can give loratadine to dogs, it is usually well tolerated and is unlikely to produce side effects such as drowsiness that tend to happen with some of the older antihistamines, such as diphenhydramine (also known as Benadryl).
Antihistamines. Diphenhydramine (Benadryl®), cetirizine (Zyrtec®), and loratadine (Claritin®) are commonly used antihistamines that relieve allergy symptoms or counteract allergic reactions. Antihistamines are usually safe but can make some dogs drowsy and others hyperactive.
How much Claritin can I give my dog? The correct dose of Claritin will depend on your dog`s weight. Although your vet can give you specifics, the general prescription is a dosage of 0.2 milligrams per pound of body weight. A small dog might get 5 milligrams per day.
When accidentally ingested by dogs and cats, antihistamine poisoning can result in clinical signs of severe agitation, lethargy, sedation, aggression, abnormal heart rate, abnormal blood pressure, vomiting, diarrhea, inappetance, seizures, respiratory depression, and even death.
While loratadine is a relatively safe drug, healthcare providers should inform patients of all the side effects associated with the medication, and medication reconciliation is necessary as with the addition or discontinuing of any drug.
The typical dosage for Benadryl in dogs is 2-4 mg/kg of body weight every 8-12 hours. Higher doses greater than 5 mg/kg can have toxic side effects such as seizures, respiratory depression and cardiovascular effects.
Loratadine is classed as a non-drowsy antihistamine, but some people still find it makes them feel slightly sleepy. Children may have a headache and feel tired or nervous after taking loratadine. It`s best not to drink alcohol while you`re taking loratadine as it can make you feel sleepy.
Loratadine reaches peak plasma concentration in 1-2 hours; the metabolite does so in 3-4 hours. Their respective elimination half-lives are about 10 and 20 hours. Onset of action is within 1 hour and duration is at least 24 hours. Once-daily dosing is recommended.
Loratadine (Claritin): ¼ mg per pound (half of a 10mg tablet per 20 lbs) once daily. twice daily. Dogs > 60 lbs: 50mg PER POUND of combined EPA and DHA daily. recommend “Welactin” due to it`s high-potency and purity.
Benadryl is safe to give your dog for allergies, anxiety, motion sickness, and vaccine side effects. Though a typical Benadryl pill is 25 mg, you should only give your dog 0.9-1.8 mg per pound of weight. Make sure that the Benadryl you`re giving your dog only contains diphenhydramine.
Can you give dogs human antihistamines? Antihistamines with the active ingredients of diphenhydramine, chlorpheniramine, cetirizine, clemastine or loratadine are usually safe for most healthy adult dogs.
Toxic doses of antihistamines may happen when a person takes 3 to 5 times the normal amount. No matter how much a person overdoses, they should seek medical help or call a poison control center.
Typically, most drugs are absorbed within 20-30 minutes after given by mouth. Vomiting after this amount of time is not related to the drug in the stomach as the vast majority, if not all, has already been absorbed. In this case do not give another dose.
You should not use this medicine if you are allergic to loratadine. Ask a doctor or pharmacist if this medicine is safe to use if you have ever had: kidney disease; or. liver disease.
Adults and children 6 years of age and older—One capsule or 10 milligrams (mg) once a day. Do not take more than one capsule per day. Children younger than 6 years of age—Use and dose must be determined by your doctor.
Dog`s Weight In Pounds: Dosage In Mg: Note that regular tablets contain 10 mg of loratadine per pill, while the children`s tablets contain 5 mg. Example: A 20 lb dog could be given between 2.4 and 4.4 mg of loratadine. This means that half a Children`s tablet could be used (2.5 mg).
This medication will take effect in one to two hours and improvement of your pet`s symptoms should follow.
The Merck Veterinary Manual recommends administering 2-4 milligrams of Benadryl per kilogram of body weight, two to three times a day.
Benadryl can be dangerous for your dog if you give too much. An overdose of Benadryl can cause seizures and other side effects. The safest way to give Benadryl is to give it according to the weight of your dog. AKC says the dose for Benadryl is 2 to 4 milligrams per kilogram of body weight, two to three times per day.
Loratadine is used to temporarily relieve the symptoms of hay fever (allergy to pollen, dust, or other substances in the air) and other allergies. These symptoms include sneezing, runny nose, and itchy eyes, nose, or throat. Loratadine is also used to treat itching and redness caused by hives.
Loratadine fully works within one hour after you take it and its effect should last for 24 hours. Your symptoms should start to improve in about 20 minutes. You only have to take loratadine once a day.
Older adults may be more sensitive to the side effects of this drug, especially drowsiness, or confusion. These side effects can increase the risk of falling. During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor before taking this drug.

Relevant Questions and Answers :

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Q. Hi My GSP just ate loratadine I estimate about 11 tablets of 10mg…….no visible side effects yet and has happened in the last hr…..help
ANSWER : A. Highly overdosed loratadine can be dangerous. You should ring your vet without delay. It may not be too late to induce vomiting and/or give activated charcoal.

Q. My dog was given a prednisone shot because of an allergie. She has had since the shot , drinking tonds of water . How long does de side effects last ,
ANSWER : A. Excessive thirst is an extremely common side effect of prednisone. The effects of the drug usually last about 3 days. If the excessive thirst continues past that point, or if there are other concerning signs, call your vet to discuss.

Q. Are there any serious counter-indications to mange medications?
ANSWER : A. In canine Demodicosis temporary sedation is the most common side effect of Amitraz, and it may not occur with subsequent treatments.

Pruritus, sedation, weakness and ataxia are also noted in some cases.

Also, Amitraz should not be used in Chihuahuas.

Mylbemicin has also been used as treatment for 90 days with a 60% success rate. Dosage might need to be increased if mites are present after the initial 30 days, and side effects at higher dosage include trembling, ataxia,vomiting and stupor.

Similar side effects are reported with treatment with Ivermectin. Collie and Collie Cross, and some herding dogs should not be treated with Ivermecting because of the effects on the Central Nervous System.

Q. If there is a side effect of blood in urine due to metronidazole, how do you treat it?
ANSWER : A. Bladder inflammation is a rare side effect of metronidazole described in human. It would be a very unusual side effect of this antibiotic in your dog. I would suggest you to contact your vet who is likely to prescribe different antibiotics for your dog.

Q. Adequan by shot or Rimadyl by pill–which is safer long term for my lab?
ANSWER : A. The two medications have different mechanism of action and different efficacy. Adequan (polysulfated glycosaminoglycans) is safer and in the long term has less side effects if used at appropriate dosage/regime and administer correctly by your veterinarian.

Do not consider Adequan a 100% safe product anyway. Side effects can include: pain at injection sites, decreased platelets numbers and kidney/liver toxicities. These side effects are not common if correct dosages are used.

Q. My vet just put my dog on an antihistamine and antibiotic. Her appetite seems to be diminished – about 1/2 of what she usually eats. Is that normal?
ANSWER : A. Side effects vary with medication, lack of appetite can be a side effect for some. I would give a quick call to your vet to let them know about the appetite, it may be a side effect or maybe something needs to be adjusted.

Q. What are the longterm effects of phenobarbitol in dogs?
ANSWER : A. The desire effect is control of seizures. The side effects which you may be referring to in your question are sleepiness, tiredness, increased thirst and appetite, weight gain, elevated liver enzymes. There is much longer list of possible side effects but they are rather uncommon.

Q. What are the long term side effects of Tramadol in dogs?
ANSWER : A. Lethargy, sleepiness, dullness, constipation are the most common side effects. As Tramadol has been used extensively in veterinary medicine only for a few years there may be more side effects that we are still not aware of.