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Dr. Peter
Dr. Peter, Veterinarian
Category: Dog Veterinary
Satisfied Customers: 30610
Experience:  16 years of internal medicine, surgery, and preventive care.
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Hi. I notice you mentioned in a previous answer that the

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I notice you mentioned in a previous answer that the dosage of Zyrtec is 1mg per 1lb twice daily for dogs with skin allergies. I've read elsewhere that this should be much lower with many saying 1mg per KG (not lb) and just once daily, with others saying a max of just 10mg once daily. My dog weighs 57 lbs.

Currently I'm giving him 20mg twice daily - hope I'm not too off? It has helped but he still bites his paws but has stopped attacking other parts of his body.

I don't actually know the cause of the allergy. It all started very quickly and he's not suffered like this ever before. We're in Thailand and there's been a lot of rain recently and dirty water so perhaps that's the issue? I've checked his body for ticks and fleas but can't find anything.

Other than biting his paws he has a water filled blister develop on his haunches (on the scar tissue) and a swollen face.

I notice on his stomach there is what looks to be a small scratch but I guess it could be the remnants of some type of bite.

Mosquitos are common in the area so I'm concerned it may be something to do with that.

So any ideas on what the cause and dosage of Zyrtecshould be would be much appreciated.

Decent veterinarians in the area are hard to come by so I'd at least like a professionals comment first before I take him to someone local.

Please advise. Many thanks!
Welcome and thanks for asking your question. My name isXXXXX am a licensed veterinarian. I am happy to answer your question today.

Friend, the dose for Zyrtec (cetirizine) can range between 0.5-1mg/kg once a day. Or, 5-10mg every 12 or 24 hours. So, for a 57 lbs Fred you can give 20mg once a day which should be the high end of the dose close to 1mg/kg once a day. If he is not doing well on Zyrtec you can try using another type of antihistamine like Benadryl (diphenhydramine) 50mg every 12 hours.
It is also important to remember that excessive licking of the paws can also be secondary to an underlying food allergy. If possible consider changing his diet to a grain free diet, free of corn, soy, gluten, wheat, barley, dairy, etc.

As far as the scratches and lesions on the body this is what you can do:

1- Need to stop him from licking or he is going to make the areas worst. Pick up an ecollar (cone) in your local pet store to stop him from licking/gnawing at affected area.
2- Pick up in your local pharmacy "Hibiclens" antimicrobial soap or chlorhexiderm scrub. Wash area with this soap 2-3 times a day. If you do not find the above soap use over the counter antibacterial soap.
3- After washing affected area as above apply a topical antibiotic like neosporin or bacitracin. Do this 2-3 times a day for the next 7-10 days.

My goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back. I am happy to address follow-up questions. Thank you for your business and I hope to work with you again soon!
Customer: replied 3 years ago.



Thanks for the answer.


He certainly doesn't seem to be doing very well with Zyrtec so I'll switch to diphenhydramine tomorrow, as you suggest. I'll also get the topical anti-biotic and soap.


His diet has not changed at all so curious as to how this could be a food allergy? Can they have reactions to stuff that they've tolerated in the past?


The only new thing in his diet is a new pack of raw hide dog chews that I've recently bought which come in array of colours - he's had them before but I've heard horror stories on dog chews/treats before.


Also, what are your thoughts on this possibly being mosquito related.


Also note : his lower abdomen (near his privates) is very hot as are the insides of his ears. He also tends to lick his penis a lot and that too looks red and inflamed.


He never cries or moans but this is really getting on top of him and he's starting to whinge, so hope we can help out.


Thanks for taking time to elaborate a little bit more.







Simon, contrary to popular belief food sensitivities/allergies are developed against food that they normally have had lots of in the past. This is why we recommend to place them on a source of protein different than what they have had in the past. In addition, avoid common allergens as listed above. I am certain if you are feeding a commercial dog food it will have some of the above mentioned ingredients. So, doing a food trial and eliminating those ingredients is always a good place to start. I am uncertain of availability in Thailand, but see if you find a "grain free diet."
The symptoms that you are describing are not related to mosquitoes. The redness and licking of genital could be part of the reaction seen with allergies. In addition, excessive licking will promote and cause inflammation. Changing the diet, anti histamine and the temporary use of an ecollar (cone) to stop the licking should provide a significant improvement in the symptoms.

Please reply if you have additional questions.

Dr. Peter
Customer: replied 3 years ago.

Ok, thanks - last follow-up question - I don't like the idea of a collar to stop him scratching. If I couldn't at least satisfy/minimise and incessant itch I'd go mad. Could I perhaps put sock on his paws instead, as they seem to be getting it worst?



Simon, the sock is not going to help. He will take it off in seconds. If he continues to lick it will delay healing, the ecollar (cone) is the only tool we have to stop the licking.

You're Welcome.

Dr. Peter
Dr. Peter and other Dog Veterinary Specialists are ready to help you
Hi Simon,

I'm just following up on our conversation about Fred. How is everything going?

Dr. Peter