Hi Andrew,

wondering if you can offer a little advice!

Thor is 3 years old and last summer started behaving quite odly, depressed, refusing to walk & loosing fur around his eyes & muzzle which then blistered.
he visited the vets numerous times and he had blood tests taken which came back he had alergies to some meats, that was back in December/january, he also had skin biopsy's done that were negative.

he had his diet changed with no sucess, he chews manicly at times at his front paws, scratches his face & sometimes refuses to walk.

this past week his back right paw has been sore, he grumbled at my partner when he touched it, he also doesnt seem to be putting full weight on it.

he is on steroids twice daily & 9 piriton a day and oil of evening primrose oil twice daily.

i have had him back at the vets tonight and the vet thinks his back paw problem is totally unrelated to the itching, though i disagree. he has renewed Thors prescription for a month & we are then to go back.

The vet has said that they are alergies & its finding a comfortable level for thor which will not affect his well being and future health problems.

Thor also has an intermittent limp in his front right paw, which after numerous tests we have not got to the bottom of, the vet thinks this is unrelated and has had this from a pup.

we have been told that his new diet can take upto 6 months to show as in the itchiness, he is now on salmon & rice James wellbeloved.

im really concerned that thor is uncomfortable and this is really dragging on costing a lot of money with no results. is there any advice that you could offer?

many thanks

Sorry should add that all of Thors alergy testing came back clear bar meat & meat deritives.

bumping this...

Hello Sarah,

Thor's history and clinical signs do make a diagnosis of allergic dermatitis quite likely, although I presume he has had skin scrapings taken to rule out mites. Zinc deficiency would also possibly present in these areas, but is not usually itchy unless there is heavy secondary infection. This is diagnosed on skin biopsy.

I usually perform a dietary trial to rule out dietary allergies, you need to use a single protein and single carbohydrate source which he has not habitually eaten before, or use a proprietary prescription diet such as Royal Canin Hypoallergenic or Hills z/d. A month is usually sufficient to show an effect if allergy exists, but it is not a common diagnosis. Blood testing is regarded as unreliable by most dermatologists for food allergy.

More likely is allergy to things in his general environment, so-called atopic dermatitis. This is a diagnosis of criteria and exclusion; cases usually start between 1 and 4 years of age, mostly in the Spring/Summer, and primarily affect the feet and face. Blood testing can be done here to detect which environmental allergens he is allergic to, such as pollens, grasses, trees, moulds, and most commonly, house dust mite. An alternative is intradermal skin testing , where small amounts of allergens are injected into the skin to see if a reaction occurs. Despite giving differing results, both the above tests give roughly similar succes rates when immunotherapy is used. This involves making a 'vaccine' to the allergens the dog is reacting to, based on the test results.

Immunotherapy doesn't cure all cases however, and some dogs don't have postive results to the allergy testing. These need to be controlled rather than cured. Steroids are cheap and usually effective, but long term use of higher dose rates can cause unnacceptable side effects. A newer approach is to use a drug called cyclosporin, marketed as Atopica. It's usually at least effective as steroids, but side effects are usually limited, and mostly involve sickness or diarrhoea. It's main drawback is cost, especially in larger dogs. A variety of other drugs can be used to redcue the dose of steroids needed, and include evening primrose oil and antihistamines. I can't over emphasise the importance of topical therapy - regular bathing of the affected areas - it washes off allergens and bacteria and yeasts which can cause secondary infection.

As you can see, each case needs to be tackled on its merits, your vet will need to decide on the combination of treatments most appropriate to Thor.

Regards Andrew.

Thanks for the reply

They first htough zinc deficiency & then changed there minds with the tests that were done, he has had skin biopsys that rule out any type of infection or mites, they were totally clear. The drug cyclosporin has been mentioned by our vet, but he did say about the expense and dosage thor would need and wants to hold off on that at the moment.
all his tests have also come back clear for environment alergies only showing a positive for the meats he can not eat.

he is taking the evening primrose oil and antihistamines plus the steroids, which i really am not happy with him taking and has been on these for around 9 months now

they diagnosed the meat alergy and now that isnt helping after a change of diet...its like they dont know!

i think as we have seen no improvement in his diet at all that may be we will try a hypo alergic food as sugested

thank you