Itchy skin can be so intolerable that we scratch ourselves until we’re sore. For dogs, who don’t understand that scratching only exacerbates the problem, itchy skin is an unbearable condition that becomes difficult to manage. Itchy skin, or pruritus as it is medically known, is one of the most common reasons for pets to visit the vet.
But while it is so common, there are many different reasons why a dog may suffer from it, meaning interventions do not always treat the cause. Itchy skin is triggered by a host of factors, including environmental, nutritional, allergic, parasitic, neurogenic and infectious. Because all of these factors relate to a negative or hypersensitive internal response to something, such as environmental causes relating to dust, pollen and mould (known as atopic allergies), and parasitic relating to the saliva of ticks and fleas, it is useful to think of them all as potential triggers.
Allergy-induced itchy skin is particularly nasty because it can be lifelong, is difficult to diagnose, and even after diagnosis, it can be resistant to many forms of treatment. On a basic level, an allergy is defined as an over-reaction of the immune system to a particular substance, with the body responding as if it were facing a threat. This response will prompt numerous symptoms, from puffy eyes and runny noses to itchy and inflamed skin. One of the most common allergies in humans is hay fever, with the immune system over-reacting to the harmless inhalation of pollen particles. As dogs are susceptible to such an array of sensitivities, pinpointing which one is causing the itchy skin becomes difficult. There may be no way of treating the allergy per se, but if you know what’s behind it, keeping your dog away from the allergen in the future should help alleviate the skin complaint.
Environmental AllergiesEnvironmental allergens are inhaled, many of which involve environmental substances we are exposed to every day. Pollen (from grass, weeds and trees), dander, dust and mould can all prompt an allergic response in your dog. Avoiding these triggers is sometimes nigh-on-impossible, especially during warm spring and summer months when our dogs are enjoying being outside. Keeping your dog inside when the pollen count is particularly high i.e. during late evening and early morning, as well as when the lawn is being mown, will reduce your dog’s exposure to these potentially harmful allergens. While respiratory problems are the most frequently experienced in human hay fever sufferers, itchy skin is the most common symptom in dogs.
If a particular allergen is identified, your veterinarian may suggest allergy shots, which can be administered weekly to help enhance the immune system’s tolerance to a particular substance. Regular shots of the allergen can make your dog less sensitive to it, the downside being it can take a good few months to notice any improvement. Pinpointing an allergen is usually done by a blood or skin test but, depending on where the itchy skin is and your dog’s other symptoms, your vet should be able to advise the most likely cause for its condition.
Contact allergies are a lot less common, but they still affect a significant number of animals. A contact allergy relates to a particular surface your dog comes into contact with that triggers an acute immune response. This usually shows through a rash that most often appears on the feet, stomach, muzzle and elbows. Whether it’s an allergy to carpet, fabric, plastic, wood (i.e. cedar), surface cleaners or lawn chemicals, your dog will need help bypassing these areas in the future. If your dog’s sleeping quarters are outside, steering clear of cedar wood dog houses and treated decking is a good idea, and tile or linoleum floors (as opposed to carpets) are the best option for indoor dogs. Cotton is safer than wool and alternative bedding fabrics for animals with allergies.
If your dog suffers from a contact allergy, they will likely experience red, inflamed skin at the site of contact, which they will scratch and bite. This behavior leaves the area raw, painful, and potentially hairless. To manage this:
Use tile or linoleum floors instead of carpets.
Opt for cotton bedding rather than wool or synthetics.
Avoid cedar wood dog houses or treated decking.
Seek veterinary help immediately if you notice bald, red, or "weeping" patches of skin, as broken skin can quickly become infected.
You may have heard about sweet itch, a condition affecting equines that is caused by an immune hypersensitivity to the saliva of the Culicoides midge. In response to foreign saliva, a horse’s immune system over-produces histamine, which, in turn, leads to itchy and inflamed skin. A horse will rub and bite at these areas so much so that the coat and skin is often worn away, leaving room for secondary infection. Similarly, fleas are a major trigger for sensitive dogs. An over-active immune system responds to the "threat" of flea saliva; for an allergic dog, just one flea bite is enough to cause a massive reaction.
The hind legs and tail end are the areas most likely to be affected by parasitic allergens. Symptoms include:
Redness of the skin (erythema)
Small bumps (papules)
Scabbing and hair loss
The best method of defense is strict flea control This involves regular treatments on your dog and insecticidal sprays in your home. VioVet stocks a range of effective flea, tick, lice and mite treatments and spot-ons, as well as insecticidal sprays for your home. While these don't "cure" the allergy itself, eradicating the allergen from the environment protects your pet from the harmful effects.
It is estimated that 24% to 49% of all canine allergies are food-related. A dog with a food allergy will exhibit classic signs of skin irritation, such as scratching the face, feet, legs, and anal area. You may also notice:
Softer or more frequent stools.
Chronic ear infections.
Isolating a food allergen is difficult because a dog may react to several ingredients at once. It is recommended to perform a food trial to rule out a food allergy cause. This involves feeding an allergenic (hydrolysed protein) diet for 6 to 8 weeks as the sole food, no treats or scavenging. If signs reduce or disappear then it is very likely a food allergen is a trigger for the allergy. Hydrolysed protein diets are advised as these are processed in such a way that the proteins cannot trigger an immune response, even if your pet is allergic to the original protein within.
While treating allergies, whether they are atopic, contact, parasitic or food-related, is not always easy, there are remedies on the market and with prescription to help manage the symptoms of itchy skin. Avoiding known allergens is the most effective measure, but identifying these can be difficult.
Allergy shampoos and supplements an be helpful. They aim to support skin barrier function, which in turn reduces the chance of allergens crossing over to trigger an allergy and aids repair of irritated skin.
Immunotherapy (allergy shots) involves testing your dog for what they are allergic to, and then safely exposing them to small amounts of these allergens over time. This helps your immune system to 'get used to' the allergens and no longer over-react to them. They should only be used alongside veterinary advice as a diagnosis of allergic or atopic skin disease with a significant environmental trigger is required before starting therapy.
There are a wide variety of prescription medications on the market that work to stop the need for your dog to itch. These come in tablet, liquid, topical and injectable form. It is best to see your local vet to discuss which option is most suitable for your specific pet, as they will need to prescribe these to you anyway. You can purchase prescription medications through our website if you request your vet to write you a written prescription for the medication they recommend. Many of these can be used safely in the long term with minimal side effects, so they can be a great solution for many affected dogs.
If you suspect allergy-induced dermatitis in your pet because of a visible sign or a behavioural change, the first step is to get him seen by your veterinarian for a proper diagnosis. It may be that an allergy is the supposed cause, but pinpointing the specific allergen involved in the hypersensitive response takes a little longer to identify. Skin and blood tests may be taken to dismiss other potential causes and your veterinarian will ask you a number of questions; if your dog suffers with itchy skin at certain times of the year, it is very likely that it is induced by an allergy. Environmental and parasitic allergens are more prevalent in spring and Summer months when the pollen count is high and when summer fleas and midges are more numerous. It may be that your dog is allergic to a certain food such as corn or poultry and needs this removing from its diet. Your veterinarian will be able to give the best advice on what to avoid and what to use to treat and manage the condition most effectively. Discuss all your treatment options with him before deciding on the course of action for your pet, and consider all potential side-effects. Even if your dog does not respond to a certain treatment, persevere. With so many remedies on the market, there is bound to be something that works!