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Dr. Kara
Dr. Kara, Veterinarian
Category: Dog
Satisfied Customers: 18134
Experience:  Over 20 years of experience as a veterinarian.
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My black Labrador has developed a scratching habit over the

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My black Labrador has developed a scratching habit over the past few months. Also his back leg will start scratching his side when his rear back is stroked. Our local vet said there are no signs on his skin of any obvious reason for the scratching so we have tried changing his food and also stop giving him bran in case of a wheat allergy, but nothing has changed. He does lie in bed and lick his rear back area, lies on the carpet rolling around and growling in pleasure! He seems OK when going for a walk although sometimes will stop and scratch his head for a few moments. He sleeps well but will lick his rear back before getting out of bed.
We are getting anxious for him and wonder if it has now become a habit. What do you think is the answer?
Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear that your fellow is itchy even with the food changes that you have made.I don't think that this is a habit, and I suspect that he is truly itchy for some reason. The leg scratching motion when his rear back is stroked is almost a reflex motion in a very itchy dogs and just tells us his back is quite sensitive.Normal looking, but itchy, skin means that the stimulus to scratch is coming from internally rather than a response to an external irritant. That usually indicates an allergy of some type. Allergies are the most common cause of itchy skin and can give him a skin crawling, all over itchy type effect which many dogs find irritating. I'll give you an allergy rundown of likely causes for skin troubles. He may have more than one allergy given how symptomatic he is now. Dogs that have one allergy often develop several with time. The effect of multiple allergies aren't additive, they actually compound one another. Even if you don't see fleas I do recommend using protection. Flea bite allergy is the most common allergen, dogs with flea allergies often tend to be itchiest at the tail base/rear back, and it only takes one bite a month to make an allergic dog scratch so I recommend using flea prevention even if you never see one again. Frontline Plus, Advantage II or Advantix are excellent. Don't use over the counter products, especially Hartz or Sargents, as most are ineffective if not toxic. Unfortunately even after the fleas are gone the allergic reaction can continue for weeks and I will discuss controlling that reaction below. Other allergens can be inhaled (like grass pollen, dust mites or molds). You can use a combination of antihistamines and high doses of omega-3 fatty acids to help with with the symptoms of flea bite and inhaled allergies. In combination fatty acids and antihistamines work synergistically, much better than either one alone. If his symptoms worsen seasonally I would think that inhaled allergens are a part of his problem. You can try:1)Benadryl (diphenhydramine only don't use the combination products with acetaminophen or decongestants as they can be toxic for dogs) at 2mg to 4mg per kilogram of body weight or one 25mg capsule per 7 to 12.5 kilograms of body weight orally every 8 hours. OR 2)Claritin (loratidine) at 5mg per 12 kilograms of body weight once or twice daily. OR 3)Hydroxyzine at 2 mg per kilogram of body weight orally every 8 hours. OR 4) Chlorpheniramine at 4mg to 8mg per dog once or twice daily.OR 5) Zyrtec (Cetirizine hydrochloride) at 1 mg per kilogram of body weight orally every 24 hours. That would be one 10mg tablet per 20 kilograms of body weight. Make sure it is NOT the formulation with a decongestant (such as Zyrtec-D) because dogs cannot tolerate decongestants.Some dogs do better on one antihistamine rather than another. Give the one you pick a week trial and if it isn't working try another. Be aware antihistamines can cause sleepiness or hyperactivity in some dogs. These side effects do wear off with repeated use.Omega-3 fatty acids are fish oil products. 3V by DVM or Derm Caps ES are good brand name products. Use the high end of the dosing schedule for your pup's weight. I recommend a dose based upon the EPA portion (eicosapentanoic acid) of the supplement as if we do that the rest of the supplement will be properly balanced. Give him 40mg of EPA per kilogram of body weight per day. For example an 40 kilogram dog could take 1600mg of EPA per day. Cool water baths with an oatmeal shampoo or chlorhexiderm shampoo (which is antibacterial and antifungal) and a conditioner with an antihistamine may help. The water rinses off allergens and the cool temperature soothes itchy skin. Do not bathe your fellow for 2 to 3 days before or after applying flea control products or the bath will interfere with the product's efficacy.Food allergy is very possible with him as well if he seems to be itchy all year round. Dogs can develop allergies to any protein or carbohydrate so even if he is only fed one thing that can be what he is allergic to. I know that you have tried to limit wheat, but many dogs are allergic to proteins, so that may be why that didn't help. Dogs with food allergies tend to lick and scratch their paws, face and ears the most, but any of the "allergy reactive areas" can be affected. Make sure that the food that you put him on is a true hypoallergenic diet. The trouble with "limited ingredient" or "low allergy" pet store brands is that the same machinery is used on multiple lots of food without sterilization cleaning in between. So for example even if a food says it has salmon and rice if the previous batch had beef and corn then you will get traces of those ingredients in your bag of food. Not a big deal if your dog isn't allergic but a waste of money thinking that the food was hypoallergenic and not good for your dog if those happen to be allergens for your dog. The veterinary brand true hypoallergenic foods are more expensive because it isn't cheap to thoroughly remove all traces of a previous food mixture from the machines used to process food.Generally what I recommend is trying to clear the skin and then adding one food item (chicken, beef, corn wheat etc) every month to see what they react to. Then we can find a regular food to try. As far as permanent diets I do tend to stick with Purina Pro Plan brands or Nature's Recipe as I find those rarely if ever have cross contamination. Purina Pro Plan Turkey and Barley or Nature's Recipe Vegetarian or Venison are pretty good products. I know that this isn't easy from personal experience (my dog is allergic to wheat) and it is time consuming, but worth it. If you choose to try testing/treating him for a food allergy I recommend that you try a true hypoallergenic diet like Hills z/d or Purina Veterinary Diets HA. No treats, flavored medication or bones while on the diet and it must be used for a least 12 to 16 weeks to see the full effects. You should see some improvement in 6 to 8 weeks. Another option if the antihistamines and omega 3's aren't enough is a product called Atopica. It suppresses the immune system a bit so it decreases allergic symptoms but it doesn't have as many harmful side effects as systemic steroids.Another option is a brand new drug called Apoquel (generic name oclacitinib) which interferes with the allergic pathway. It works very quickly to stop the symptoms of an inhaled allergy, but does NOT work for food allergies as those are stimulated via a different allergic pathway. Most dogs are reported to be much more comfortable in a day or so. Unfortunately it is on backorder now due to overwhelming demand, but it is something to keep in mind for the future if he continues to have trouble.If you are interested discuss these medications with your veterinarian as they are prescription products. Another option if you are interested, is trying immunotherapy. Your fellow would need to be tested to determine exactly what he is allergic to, and then he is given small amounts of the allergen to build up his tolerance to it, increasing the amount of allergen in the injection incrementally so that his immune system no longer responds to it. This isn't a quick fix, it takes time to slowly build up their tolerance and as he develops new allergens things may need to be added, but it is an option. If it's been a while since his last exam parasites like cheyletiella, demodex or sarcoptes mites should be looked for by your veterinarian as well if he isn't improving as they can lead to very itchy skin. Please let me know if you have any further questions.
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Customer: replied 2 years ago.

Many thanks for you long comprehensive reply. I really do not think I can take it all in as it is obviously a complicated set of remedies.

We apply every 28 days Advocate Spot on 400 for the flea and parasite control purchased on line from, although supplied in the correct packaging is it possible this could be substandard?

I again inspected his skin last night and there was 1 red mark on his back which I cannot find again today. Early this morning when he got out of bed his top rear back was wet from licking so I gave him a Piriton tablet and he has calmed down now. Perhaps a month ago the vet did say to give him Piriton and after 10 days with no response we stopped.

I think I will make another appointment with the vet and show him your report and take it from there.

Many thanks and I may contact you again.

Stephen Cluer

Advocate Spot On is a very good product too, it is known as Advantage Multi in the US. There are counterfeit products out there that look just like the real thing. In the US it is a prescription product, I don't know if that is the case in the UK, and the manufacturer has told us that they do have trouble with substandard counterfeit products being sold without the need for a prescription. So it is possible that the product that you have is fine, but it's impossible for me to be sure.I think that he does have some sort of allergy, and he may have more than one given the amount of licking and scratching that he is doing. I believe Piriton is the trade name for chlorpheniramine in the UK. That is fine to use and I would add an omega 3 fatty acid supplement along with it.Please let me know how he comes along or if you have any further questions.