What to do if your dog is itching. Treating scratching in dogs: the main thing the owner needs to know Veterinary anti-scratching medication for dogs

What causes itching in dogs?
Main symptoms.
Treating itching in dogs.
Prevention - how to prevent the development of the disease in your pet.

Have you noticed that your pet is starting to itch much more often? Does the dog not just lightly scratch itself with its paw, but frantically tear its ears or sides? Do you even have scabs and scratches on your skin? All this suggests that the dog has severe itching. To help your pet, you first need to figure out why it appeared.

What can cause itching in dogs?

One of the most common provoking factors is food and non-food allergies. Plant pollen, household dust, and aggressive household chemicals can cause itching in a dog.

Food allergy has various manifestations, but in terms of frequency of distribution it is one of the most likely causes. Even if you feed your pet a commercial diet, this does not mean that he is immune from food allergies. The composition of industrial feeds quite often includes components that cause an individual reaction in the dog’s body in the form of itching, gastrointestinal disorders, conjunctivitis and other diseases.

These components include:

artificial colors and flavors;
preservatives;
toxic compounds.

The latter are transformed during a chemical reaction from seemingly safe substances. For example, the antibiotic oxytetracycline, which is actively used in industrial animal husbandry, after a cycle of reactions becomes a substance that provokes the development of allergies, gastrointestinal disorders, and skin diseases in humans and animals.

Some dog breeds are more prone to food allergic reactions:

snow-white animals;
French and English bulldogs;
boxers;
cocker spaniels;
dachshunds;
German Shepherds.

Other possible causes of itching in dogs may include:

You can detect itching in dogs, even without constantly observing the animal, by the following signs:

minor scratching (skin damage) on different parts of the body. May appear as small scratches, pink or reddened skin;
local increase in body temperature (in areas of scratching);
severe anxiety of the animal;
Possible hair loss in areas where scratching occurs.

the head, neck and lower third of the back are the habitat of lice;
only the lower third of the back has fleas.

If your dog's itching is caused by an allergy, it may be accompanied by other symptoms:

redness of the eyes and watery eyes;
otitis (inflammation of the middle ear);
gastrointestinal disorder.

Treating itching in a dog

A veterinarian must prescribe a treatment regimen based on the cause that caused this condition. A special therapeutic diet is designed to alleviate the condition. During illness, it will provide the animal with all the necessary nutrients, cover the need for vitamins and minerals, without overloading the body. Your pet will be able to devote most of its energy to fighting the disease, and not to digesting food that is unsuitable for it.

The veterinary diet basically contains meat from farm animals or fish caught in the open sea. The need for carbohydrates and fiber is met by vegetables and grains grown without the use of pesticides. Fruits and berries complement the taste and compensate for the lack of vitamins, macro- and microelements. Such a diet will help the animal recover without loss, improve the functioning of the gastrointestinal tract, and the condition of the skin and coat. It also helps strengthen the cardiovascular system, joints and muscles. The diet should be selected based on the pet’s age, activity level and illnesses. A veterinarian will also help with this.

Prevention - how to prevent the development of the disease

Good immunity and proper nutrition help cope with diseases. Provide your pet with an appropriate level of activity and take care of high-quality food. A specially selected veterinary diet that helps during illness also works well after it.

In addition to high-quality ingredients, the composition includes unique components - extracts of medicinal plants. Small phytocapsules contain extracts of papaya, pineapple, aloe vera, oregano, plantain and other plants. After all, medicinal herbs are a real storehouse of nature. Extracts of these plants, certain fruits and berries have anti-inflammatory, immunomodulatory, and antiseptic effects. Such supplements help eliminate inflammation, relieve pain, normalize digestion, and calm your pet. Medicinal food will complement the main treatment regimen, improving the animal’s well-being and providing it with energy for walks with its owner.

Itchy skin in a dog occurs as a result of excessive irritability of the skin. It can spread throughout the entire body or affect only certain areas of the skin.

The dog scratches itself with its claws and bites, rubs against door frames and other objects, scratches itchy places until it bleeds. In this case, scabs form on the animal's body.

Causes of itching in dogs

subcutaneous mites.

If so, this may be a sign of ear mites. A dog may itch even if it has some kind of skin disease. There can be a lot of such diseases. In order to establish the exact cause, it is necessary to take the animal to a veterinarian and thoroughly examine it.

The accuracy of the diagnosis will determine the prescribed treatment and the speed of the dog’s recovery.

Treatment for itchy skin in dogs

If there is extensive damage and severe itching, it is necessary to give the animal corticosteroid hormones:

hydrocortisone,
cortisone,
dexamethasone,
prednisolone and others.

Only these drugs can relieve severe itching within the next 4 to 12 hours. However, such hormones have potentially dangerous side effects, so they should not be used for long - no longer than a week and in the most serious cases. For diagnosed allergies, antihistamines are used.

Although their effectiveness in dogs is only close to 40%. At the same time, it is necessary to try more than one option of antihistamines, giving each one for two weeks. This way the most acceptable one is revealed. Antihistamines also have side effects, they cause drowsiness, but are less dangerous compared to corticosteroids.

Most often used:

tavegil,
diphenhydramine,
suprastin,
Diazolin.

Enriching food with fatty acids also helps relieve itching caused by allergies. First of all, these are fish oil and evening primrose oil. These are natural anti-inflammatory agents that relieve itchy skin. They can also be used in combination with antihistamines.

An animal’s natural reaction to a stimulus is to try to get rid of it. To achieve this, dogs begin to itch and constantly lick themselves.

If you have such symptoms, the first task is to check your pet for fleas. If they are not found, then it means that such symptoms are caused by some other diseases or problems.

There are a number of reasons that fit these symptoms:

Most often these are skin problems, some kind of irritation or reaction caused by one factor or another.
Also, do not forget that dogs, like people, have food allergies.

If the owner notices such symptoms, one should not hesitate and let everything take its course. Such symptoms may go away on their own, but it is better to check and find out what the reason is. It is best to contact your veterinarian for this. Veterinary clinics have dermatologists who deal with similar problems.

Why does a dog itch and chew itself?

The answer to this question is quite simple - this is the animal's only reaction to the stimulus. For a more detailed understanding, dogs can easily be compared to small children. If they get itchy, they can scratch the problem areas until actual wounds form.

The animal’s body is not always able to deal with the problem on its own. Therefore, the pet begins to chew and scratch itself to get temporary relief. It is worth saying that even domestic and completely healthy dogs can itch and chew themselves from time to time, there is nothing wrong with that.

But if this happens regularly, the animal tries to rub against some objects and shows its discomfort with all its appearance, it is necessary to understand the causes of the problems and begin to solve them as quickly as possible.

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Causes

Itching and hair loss in dogs can be caused by the following reasons:

These are the three main reasons why dogs may experience itching and hair loss. It is necessary to understand that each of these points includes a huge variety of different diseases or irritants.

Let's now try to take a closer look at the most common cases that are characterized by similar symptoms, and also figure out how to deal with such problems.

Fleas in the litter

It is very common for dogs to itch after flea treatment. For example, a dog picked up fleas on the street and fought them with shampoos. In this case, in the near future, fleas will not be able to live on the animal’s body. The problem may be that they were left in the bedding or in the kennel.

If the dog lives outside in a kennel, then it also needs to be treated with special products (which are sold in veterinary pharmacies) or washed well with detergents.

Allergy

Hair loss and itching can often be caused by an allergic reaction in your dog. Most often this is associated with food. This can be noticed and understood in cases where a pet begins to eat something it did not eat before (for example, other food). In this case, you need to change your diet.

Scabies and lice

Scabies and lice are small, flesh-colored bugs that live on your dog's skin and fur. They most often affect puppies and older dogs. Young dogs are susceptible to such problems only in cases of weakened immunity.

This disease is characterized by scratching on the abdomen, elbows, inguinal folds and ears. The main symptoms are that the fur becomes brittle and dry, often matting. Dry crusts or scales can also be found on the skin.

Trombiculide and demodicosis

Similar problems are caused by tick larvae in dogs. Diseases manifest themselves quite clearly and it is very difficult not to notice them. The skin around the eyes and near the mouth is most often affected. It becomes red, hair falls out in these places, and the skin becomes covered with pustules in these places.

Insectoacaricidal drops are used to get rid of ticks. you can see in this article.

The sooner you start treatment, the easier it will be. In the later stages, it is often very difficult to cure a dog without complications and consequences.

Fungus

Fungal diseases appear most often in dogs that have not been vaccinated or in animals with severely weakened immune systems. Such diseases are often dangerous and can be transmitted to humans.

The main symptoms of fungus are:

severe itching;
redness;
receding hairline is round in shape.

For treatment, it is best to vaccinate or treat the dog with a special course of medications (tablets and injections). In addition, it is recommended to use special shampoos.

Hormonal problems

Dogs, like humans, can experience hormonal problems and disruptions. Such hormonal imbalances can be congenital or acquired.

To establish a diagnosis need to get tested(blood). Based on the study, the veterinarian will be able to prescribe treatment. Most often, such diseases manifest themselves not only in hair loss or itching, but also in behavior changes, decreased activity, weight gain or loss.

Lack of vitamins

Lack of vitamins often causes hair loss. The dog should receive a full diet of all vitamins.

To do this, you can buy similar vitamins from the pharmacy from time to time or constantly give food that is full of essential vitamins.

Vitamin deficiency in dogs most often occurs in winter and spring. In addition to hair loss, the animal begins to lead a more passive lifestyle, enjoys and plays less, and may lose weight.

Decreased immunity

Decreased immunity– the main enemy of any living organism. Most often this happens due to poor nutrition or various diseases. Decreased immunity is typical for older dogs; problems also arise in puppies, because their immune system is not yet fully formed.

Reduced immunity can not only harm the dog in itself, but also increases the risk of getting other diseases.

Stress

Pets can experience serious stress, which can cause depression, lack of appetite, hair loss and many other problems.

Such stress can be caused by various reasons. For example, this could be the loss of a loved one or another close animal (long-term departure), moving to a new place, and much more.

In such cases, it is necessary to give the animal a lot of attention and affection, try to understand the cause of the stress and eliminate it as much as possible. It is also worth giving your animal vitamins and proper feeding during periods of stress, because stress can cause serious illnesses.

Ringworm

This disease is more common among street dogs. However, it can also occur in well-groomed pets. The causative agent of the disease is the fungus Trichophyton.

The obvious symptoms of lichen are red spots and itchy skin. In such areas, hair begins to fall out. Also, these areas are covered with dry crusts. Over time, pus begins to form under these crusts. If the disease is advanced, it is very difficult to treat.

The disease seems simple, but it must be taken seriously. It is imperative to contact specialists as quickly as possible. They will be able to make an accurate diagnosis and tell you how to deal with the disease.

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What to do about this problem?

If dogs become itchy and hair begins to fall out, action must be taken quickly. First of all, you should think about the possible cause of the disease. Very often it is on the surface and can be solved very simply even at home.

If you cannot solve the problem within a few days, you must contact a veterinary clinic for examination and consultation with specialists.

How to treat?

If the cause has been accurately established, then you can proceed to treatment. The best treatment is medication. Knowing the disease, you need to go to a veterinary pharmacy. There specialists will help you choose the right medicine.

Often treatment may not be necessary. For example, the problem may be an unhealthy diet or lack of vitamins. In such cases, it is necessary to fix the problem as quickly as possible.

Prevention

Prevention of dog diseases is a series of simple procedures that the owner should carry out regularly:

Visit the veterinarian for a general examination at least 2 times a year.
It is mandatory to have all necessary vaccinations from a very early age.
It is necessary to regularly groom your dog by bathing and brushing it.
From time to time it is necessary to independently examine the dog for problem areas on its skin.
Monitor your pet's behavior and mood changes.

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Conclusion

To summarize, I would like to say that most diseases associated with itching, hair loss and other symptoms can be prevented. If they arise, then you need to act immediately.

Such diseases are treated quite simply at the initial stage. If the problem is neglected, it can seriously harm the animal’s body.

Itching is an extremely unpleasant sensation that causes dogs to have an irresistible urge to scratch. In many cases, this may be the first symptom of a disease that has arisen in a pet, so it cannot be ignored.

In different cases, the itching can be local in one or some places or cover all parts of the body at once.

The reasons for its appearance can be different, mainly the following:

Diagnosis of itching

Until the causes of this disease are identified and an accurate diagnosis is made, symptoms can only be treated with local remedies.

Treatment of itching of various etiologies

Complex treatment is prescribed only after the veterinarian has made an accurate diagnosis; its features and specificity depend on the existing disease, since itching itself is usually only one of the symptoms.

Depending on its causes, the following treatment may be used:

If there is increased irritability and sensitivity of the skin, it is necessary to normalize the dog’s nutrition. The diet should be balanced and contain a significant amount of vitamins and minerals; fatty foods and spices are recommended to be completely excluded. Ointments prescribed by a veterinarian are also used, and an alcohol solution of tar is also used, which is prepared in proportions of 1:10. During treatment, water procedures with soothing soap are necessary at least once a week, as well as temporary exclusion of meat from the diet.
If the itching was caused by a wet variety of lichen, then drugs such as Sulfur and Mercurius are used for treatment. They must be used in accordance with the instructions that come with these products; they can be taken either internally or applied externally to the affected areas. As additional measures, bandages with medicinal ointments and water procedures with creolin soap are used. To speed up the treatment process, it is necessary to temporarily completely exclude meat products and potatoes from the diet.
When itching caused by lichen sicca, it is necessary to isolate the dog from other animals, since this disease is extremely contagious and there is a high risk of infection of other pets. The animal needs to be bathed and washed as often as possible with regular soothing soap, and before going to bed, treat the affected areas with linseed oil. Phosphorus 3 or Dulcamara 3 is added to food, the daily dosage is no more than five drops.
Scabies and scab are extremely unpleasant diseases that progress very quickly, the itching is so strong that soon bald spots appear on the animal’s body from frequent scratching. The disease is extremely contagious, so mandatory isolation of the dog from all healthy pets is required. During treatment, a change in diet is necessary; all food should be light, but at the same time nutritious; oatmeal is good. Every other day, water procedures with creolin soap are required; in addition, affected areas on the dog’s body are treated with it. Treatment with linseed oil is also acceptable; this will soften existing scabs, which will speed up the healing process. Sulfur 3 or Mercurius 3 is added to food, the dosage is determined in accordance with the instructions.
If you have a food allergy, there are a number of difficulties, since even with the help of tests it is extremely difficult to determine what exactly caused it. It is necessary to constantly change the dog’s diet, identifying allergens by elimination, on the basis of which preventive diets are built. If the allergy is caused by non-food factors, but in the vast majority of cases it is chronic and cannot be cured. In such a situation, the veterinarian prescribes medications and determines the specific conditions of detention in order to improve the dog’s condition and relieve it of incessant itching.

In most cases, treatment occurs using various means and drugs; their different groups and effectiveness of use are discussed below:

Follow-up and prevention

The presence of itching causes great discomfort to the dog and disrupts its normal existence, and identifying the causes and curing it is often quite difficult.

Common manifestations of itching include scratching on the body, biting, self-injury, frequent licking of paws and claws, and scratching of the perineum. The dog rubs its head on the carpet or furniture and often rolls onto its back.
Identifying areas of itching helps in differential diagnosis of its causes.

During the initial examination of a dog with itching, the veterinarian conducts an examination of skin scrapings and a cytological examination of the surface of the skin.

The author does not recommend using glucocorticoid drugs that temporarily relieve itching to eliminate itching, since their use makes it difficult to make a correct diagnosis. In addition, the use of glucocorticoids is contraindicated in case of skin infection.

Introduction
Dog owners often seek veterinary help for itching in their pets, both in general veterinary clinics and in specialized dermatological veterinary departments. Itching often becomes a difficult problem for both the pet owner and the veterinarian. In such cases, it is best to gradually, step by step, carry out appropriate research methods aimed at identifying the causes of itching, and constantly inform the pet owner about their results.

Differential diagnosis of most cases comes down to finding out whether itching is a consequence of:

Before performing clinical tests, a careful history should be taken to assist in the differential diagnosis.

Symptoms of infectious diseases caused by Malassezia pachydermatis or Staphylococcus intermedius always suppress the primary skin disease. In such cases, the effect arising from the use of general antibacterial or antifungal therapy helps to establish the primary disease.

For example, the disappearance of pyoderma after a course of antibacterial therapy, but the persistence of itching indicates that the itching was caused by a primary skin disease, against which a secondary infection occurred. If after antibiotic therapy the itching also disappears, we can assume that the primary skin disease itself did not cause itching (for example, endocrinopathies, demodicosis, follicular dystrophy). Sometimes there are patients in whom recurrent superficial pyoderma is only a manifestation of an allergic reaction.

Allergic skin diseases are usually associated with the age at which they first appear and the seasonality of exacerbations (Table 1). Sometimes they manifest themselves in the form of rhinitis, sneezing and conjunctivitis against the background of atopic dermatitis or diarrhea accompanied by vomiting and flatulence, as happens in the case of food intolerance. Recurrent otitis is considered a dermatological disease and is seen in most dogs with atopic dermatitis or food intolerance. Additionally, many dogs suffering from recurrent pyotraumatic dermatitis have a primary allergic skin disorder.

A practicing veterinarian needs to check with the owner whether his dog is itching or simply does not allow himself to be touched. Be sure to ask how long and thoroughly the dog licks its paws - many owners consider this behavior of the animal simply a manifestation of its cleanliness. When a dog behaves restlessly, rubs its head on furniture or the carpet, and often rolls on its back, all these signs indicate that the animal is itching.

It should be noted that true contact allergies in dogs are rare. This phenomenon is most often observed when using topical medications, such as ear drops (Figure 1). In such cases, at the beginning of therapy, the otitis media smoothes out, but then the animal’s condition worsens. Upon cytological examination of scrapings from the auricle, the number of infecting organisms decreases, but itching and erythematousness remain.

Figure 1. Contact dermatitis on the inside of a dog's ear caused by long-term use of ear drops.

Clinical symptoms
Clinical signs of itching are scratching and bald areas caused by self-injury of the animal.

With superficial infection with staphylococci, the following are usually observed:

pustules,
papules,
areas of baldness,
skin lesions in the neck area.

The distribution of itching zones is a good diagnostic sign and helps to identify the cause of the disease.
The distribution of itching zones for major skin diseases is shown in Tables 1 and 2. Foci of infection by fungi of the genus Malassezia spp. often localized in closed areas of the skin, for example, in skin folds on the head and paws. The affected areas feel greasy to the touch and have an unpleasant odor (Figure 2).

Figure 2. Diaper rash dermatitis on the abdomen of an obese dog. Cytological examination revealed colonization of the skin with M. pachydermatis.

Often fungi affect the claw beds. This causes some dogs' nails to become discolored and brittle (Figure 3). In the author's experience, in some animals, infection with Malassezia causes very severe itching in the lips, which are moderately erythematous and slightly scabby.

Figure 3. Discoloration of a dog's nails due to infection of the nail bed by the Malassezia fungus. After treatment, the color of the claws is restored.

Wetting the itchy areas with saliva, which occurs during licking, helps to clarify the nature of their distribution, as well as to assess the degree of chronicity of the disease (Figure 4). In otitis media, which is mentioned here because it usually accompanies allergic skin diseases (such as food intolerance or atopic dermatitis), the dog suddenly begins to shake its head frequently. In many cases, by the time a dog contacts a veterinarian, a secondary bacterial or fungal infection of the skin has already developed, which greatly aggravates the course of otitis media. In this case, dogs usually scratch their ears, rub them on furniture or on the carpet.

Figure 4. Discoloration of the paws of a dog with atonic dermatitis caused by constant licking of the paws.

Diagnostic tests
The simplest and most diagnostically important tests that should be performed immediately during the first visit to the veterinarian are a cytological examination of skin scrapings and a histological examination of the skin surface.

Figure 5. Itching and flaking on the facial part of the head of a young pug due to ear mite infestation.

Skin samples should be taken directly from the itch.
For microscopic examination, you should take not only skin scrapings, but also hair.
Before collecting skin samples, fur from the lesion should be removed.

The most common microbial skin infections, such as Malassezial dermatitis and staphylococcal pyoderma, are usually diagnosed by the presence of characteristic clinical symptoms and by cytological examination of skin samples from the lesions. In cases where the animal has large areas of baldness, infection with dermatophytes is suspected. Infection with fungi Microsporum gypseum and Trichophyton spp occurs less frequently. These microorganisms are less suited to living on the skin of dogs, and when infected, an inflammatory reaction occurs, accompanied by severe itching. To identify the type of infecting dermatophyte, hair and scales are taken from the lesion and cultured in a special dermatophyte detection medium or Sabaround dextrose agar.

Control therapy
Control therapy provides valuable information and helps clarify the diagnosis, which is why it is often used in dermatology:

A dog or cat suffers from itching in the lumbar region, which occurs with seasonal exacerbations, but fleas cannot be identified. However, the diagnosis of “allergy to flea bites” is not removed. In this case, the pet owner is advised to treat all pets with which the patient may come into contact with flea treatment. In addition, it is recommended to treat the house, car and animal walking area with drugs that block the growth of insects. The author prefers to use insecticidal agents that act on adult insects. Usually this technique gives the optimal effect. After 4-6 weeks, the dog is re-examined to determine the response to the therapy.
In a dog with suspected scabies, the presence of scabies mites could not be detected during a general clinical examination. However, control therapy with an anti-scabies drug was recommended and continued for 4 weeks. In the author's experience, a single treatment with ivermectin is ineffective for the complete destruction of scabies mites, therefore repeated treatments with selamectin at 2-week intervals are usually recommended.

Note: In some countries, veterinarians perform serological testing for antibodies to scabies mites according to a method developed by Dr. Bornstein's laboratory at the University of Gothenburg, Sweden. This study allows you to make an accurate diagnosis.

The absence of pustules in a patient does not eliminate the suspicion of superficial pyoderma or bacterial folliculitis. Staphylococcal infection has many clinical forms, depending on the stage of the process and the structure of the skin at the site of the lesion. In particular, it can manifest itself in the form of pustules, papules, lesions on the neck in the form of a collar, and patchy baldness (Figure 6).

Figure 6. Bacterial folliculitis on the body of an English Bulldog. Based on clinical symptoms alone, it is almost impossible to distinguish it from demodicosis or dermatophytosis.

Attention! The author does not recommend the use of glucocorticoids during control therapy. These drugs bring short-term relief to the patient, but make it difficult to diagnose and identify the cause of itching, since glucocorticoids reduce itching in skin diseases of various etiologies. In case of skin infection, the use of glucocorticoids is strictly contraindicated.

Further evaluation becomes necessary if secondary infections or otitis media begin to recur. It makes sense to wait time to evaluate the seasonal nature of the disease in young dogs.

Figure 7. Young boxer with severe facial itching and food allergy.

Since the author practices in North Carolina, the majority of his patients are young Labrador Retrievers. In most cases, he had to deal with severe food allergies in dogs, accompanied by symptoms of dysfunction of the gastrointestinal tract in the form of periodic vomiting, diarrhea and flatulence.

Feed intolerance includes food allergy (the pathogenesis of which is immunological in nature) and feed intolerance itself (in the absence of an immunological component in the pathogenesis of the disease). Most dogs experiencing itching due to food intolerance fall into the first group. In many animals, an allergic reaction to food is combined with allergies caused by environmental allergens.

The “gold standard” for diagnosing food allergies is to switch the animal to a diet with a new source of protein until the clinical symptoms of the disease disappear. Next, provocative feeding of the dog with the old diet is carried out. If clinical symptoms reappear, a diagnosis of food allergy is made. The diagnostic diet should be selected in such a way that it does not contain proteins that the animal previously consumed. The question is debated as to what is better to use - a factory-produced or home-cooked diet. According to the author’s experience, the desire of owners to prepare food for their animals themselves reflects the national specifics of some peoples. However, the recommendation to use homemade diets under the pretext that animals are allergic to certain ingredients of ready-made diets is not justified. The literature (2, 3) describes 8 dogs that tolerated home-prepared diets well, but did not tolerate ready-made food of similar composition. Reference (4) indicates that 47-85% of dogs with food allergies are intolerant of one or more pre-prepared diets containing a limited number of antigens. However, this work did not establish whether the protein contained in the diets was new for dogs, or whether it was the protein that caused allergies when using the proposed diets. At the same time, food additives, proteins whose immunological properties have changed during the production of the feed, as well as components of the diet packaging can cause an undesirable reaction to the finished diet.

While keeping an animal on a diagnostic diet, you should not give it treats or handouts from the table.. In addition, potential allergens may be contained in flavorings in hygiene products (for example, toothpastes), preventive medications against heartworms and fleas, and in some therapeutic agents in tablet form. Recently, in a group of dogs with spontaneous food allergies, an adverse reaction to a flavoring additive in a monthly deworming product was identified (6). The animal should be kept on a diagnostic diet for at least 6 weeks. In some cases, significant clinical improvement occurs only after 8-10 weeks of using the diet, so if the first signs of improvement appear after 4-6 weeks, this feeding regimen should be continued. The transfer to a diagnostic diet is carried out gradually, over 3-5 days. This regimen prevents gastrointestinal upset and gives the animal time to get used to the new food.

In some cases, it may be necessary to treat associated complications, such as superficial pyoderma or inflammation of the outer ear of a fungal or bacterial nature. In all cases, the necessary drug therapy is first carried out, and only then, after some time, the patient is transferred to a diagnostic diet. The duration of this diet is at least 2-3 weeks. The final diagnosis of “food allergy” is established on the basis of the resumption of clinical symptoms after the patient is switched back to his usual food (or its individual components).

The diagnosis of atopic dermatitis is made based on medical history and the nature of clinical symptoms (Table 1), after excluding other causes of itching. The severity of itching in atopic dermatitis varies greatly. In mild cases, symptomatic treatment in seasons when there is an exacerbation is sufficient. In more severe cases, with a long course of the disease, intradermal skin examination or serological determination of the antigen is performed, followed by desensitizing therapy.

Some Causes of Itching in Dogs
Itching associated with the formation of papules, nodules and peeling of the skin may indicate the formation of neoplasia. For example, epitheliotrophic lymphosarcoma may present as erythema and desquamation accompanied by pruritus that does not respond to normal doses of glucocorticoids. At the beginning of the process, the distribution of affected areas resembles the clinical picture of atopic dermatitis, with only older dogs becoming affected (Figure 9). Mast cell tumors may also be itchy. The cause of itching in this case is active substances with a pro-inflammatory effect that enter the skin due to degranulation of some cells. In some cases, severe itching is accompanied by breast cancer due to inflammation (Figures 10 and 11). In cases where the diagnosis excludes the usual causes of itching, a skin biopsy of the lesions should be performed or consult a specialist.

Figure 8. Lichenification of the pinna and external auditory canal in an 8-year-old poodle with chronic, late-diagnosed food allergy.

Figure 9. Erythroderma on the face of a 12-year-old spaniel suffering from epitheliotrophic lymphoma.

Figures 10 and 11. Areas of itching on the abdomen and back of an 11-year-old female spaniel due to inflammation accompanying a cancerous tumor of the mammary gland.

Summary
The main methods for diagnosing the causes of itching in dogs are given in the table:

Table 3. Diagnostic plan for itching.

Literature

Curtis, S. F. Diagnostic techniques and sample collection. Clinical Techniques in Small Animal Practice 2001; 16(4): 199-206.
Jeffers. J., Shanley, K.. Meyer. E. Diagnostic testing of dogs for food hypersensitivity. Journal of the American Veterinary Medical Association 1991: 198: 245-250.
White. S. Food hypersensitivity in 30 dogs. Journal of the American Veterinary Medical Association 19S6; 188:695-698.
Leisira, M. H. G.. Markwell, P. J., Willemse, T. Evaluation of selected protein source diets for the management of dogs with adverse reactions to foods. Journal of the American Veterinary Medical Association 2001; 219: 1411-1414.
Jackson. H. A., Hammcrbcrg. B.. Jackson. M.W et al. Evaluation of the clinical and serum IgE responses to oral challenge with cornstarch, corn, soy and a soy hydrolysate diet in dogs with known food allergy In: The Annual Meeting of tfte American Academy of Veterinary Dermato/og)" and American College of Veterinary Dermatology , April 2002. New Orleans, USA.

Hilary A. Jackson BVM&S, DVD, MRCVS, DipACVD
Assistant Professor, Department of Veterinary Dermatology, College of Veterinary Medicine
North Carolina State University, USA