Identifying the appropriate treatment

In cases of cAD, the function of the skin is compromised leading to loss of water through the skin [2]. This is known as barrier dysfunction and is thought to be one of the problems that contributes to skin inflammation and itching, which in turn lead to scratching, licking, rubbing and eventually infection [1].

Barrier dysfunction can be managed in several ways. Twice weekly bathing with shampoos containing linoleic acid (e.g. Allermyl; Virbac) can be helpful for many dogs [1]. Depending on your dogs’ condition, other shampoos may be prescribed to tackle secondary infections (bacterial or fungal); these can worsen the function of the skin barrier unless counteracted with the additional use of a suitable moisturiser. Other treatments include use of fat containing substances applied to the skin (e.g. Allerderm; Virbac), or those containing essential oils (such as Dermoscent; LDCA) [3,4].

Essential fatty acids (EFA) can be provided in the dog’s diet, either as a supplement or in a food specially designed for dogs with cAD and are thought to help support the skin barrier [1]. Evidence for their effectiveness is not clear-cut, mainly due to the wide variation in types of EFA available and the doses provided. Possible benefits are likely to be slow to occur, so EFA’s are not recommended for use of short-term flare-ups [5]. If you are planning to use EFA’s in your treatment regime it is recommended that they be sourced through your vet and used at the recommended dose.

There are many ways in which you can help manage your dog’s condition. Depending on the actual cause of your dog’s allergy there may be steps you can take to help manage your dog’s condition.

Dust mite allergy

Dust mites are commonly found in soft furnishings such as sofa’s and beds, and in humid areas of the house. To reduce your dog’s contact with them you should avoid carpeted flooring, and opt for wipeable, non-fabric dog beds, or material such as Vetbed and weekly washing at 60 degrees. It may also help to keep them from spending too much time in known humid sections of the house (i.e. kitchens and bathrooms). Ideally, dogs with skin allergies should not be let onto upholstered furniture, including sofas and beds, to minimise their exposure to house dust mites.

Pollen Allergy

Pollen allergic dogs are most symptomatic in the spring and summer. Walks are a necessity so can't be avoided but washing or wiping down your dog regularly after walks may help to remove pollen from their fur; but make sure to dry them thoroughly after especially between their toes. Try and dry their washed bedding inside the house if you can when the pollen is high. Additionally, air purifiers that filter out pollen may be useful.

Glucocorticoids are a form of steroids that reduce inflammation caused by the immune system response to allergens. They come in both oral, and topical forms including tablets (e.g. Prednisolone or Methylprednisolone), creams (e.g. Isaderm, previously known as Fuciderm) and sprays (e.g. Cortavance; Virbac). Glucocorticoids are commonly used at some stage for treating cAD due to their fast acting control of signs, but in some circumstances can lead to numerous adverse effects (including increased susceptibility to skin infections), so their use is often limited to short-term treatment of flares, however oral glucocorticoids have been recommended for long-term use at low dosages to minimise adverse effects [5].

Another form of treatment available since 2002 is an immunosuppressant medication known as ciclosporin (Atopica; Novartis Animal Health). It has been reported to have fewer risks than steroid treatments, can be used alongside other treatments, and is recommended as a long-term treatment for cAD [5,6].

A relatively new drug to the UK market is oclacitinib (Apoquel; Zoetis), which is an oral treatment designed to reduce the itch associated with cAD, which in turn reduces scratching and broken skin. As with ciclosporin, it has been reported to cause fewer long-term side effects than steroids, and can be used alongside other medications as a long-term treatment [5,7].

A new drug was released in 2017 called Cytopoint. This is an injectable solution that targets the sensation of itching to help relieve the itch. Dogs’ treated with Cytopoint typically receive an injection every 4-8 weeks.

Many owners in our project reported concerns about the long-term side effects of medication. One way to help reduce any risks that many owners reported being useful was to plan a stepped approach to treating their dog. Whilst the dog’s skin problems were mild, they might reduce how much medication the dog was on, and then use medications such as steroids or Apoquel only when the dog had a flare-up. This may not be suitable if your dog has particularly severe allergies, in which case they may need to be on medications long-term. It’s important to tailor your treatment plan to your dog’s specific needs. Some dogs may not respond well to one type of medication, but thankfully with the various options around there may be a different one that does work for them.

Allergen-specific immunotherapy is considered to be a safe and somewhat effective method for reducing the symptoms of cAD [8]. It does not currently have marketing authorisation in the UK but is licensed for sale in Europe and can be imported into the UK through veterinary clinics. The treatment is administered through a series of injections, which slowly increase the levels of specific allergy causing compounds the dog is allergic to (the allergen) in the dog’s system. This slow increase of the allergen is thought to increase tolerance for the allergen and reduce subsequent response when it is naturally encountered. Benefits from the treatment may not be seen for months after beginning treatment, and as such must be committed to for at least one year in order to make sure it is having the desired effect [8].

Anithistamines are an unlicensed treatment in dogs [1] and have been shown to be of limited benefit for the treatment of moderate to severe cAD [9]. They are suggested to be more beneficial for treatment of mild cAD and should be given before a flare-up occurs [5].

Dogs will scratch or groom themselves when they experience stress. Often this is a simple case of a few scratches whilst in the vets, but in some cases, stress experienced in response to an unstable situation can manifest itself in a similar manner to atopy. In this case, over grooming and scratching leads to skin breakage (lesions), which are then open to secondary infections. This is known as psychogenic dermatoses [10].

Typically, dogs with psychogenic stress-related dermatoses will scratch only when they are awake and can be distracted from their scratching with food or play, however this isn't enough for diagnosis as many dogs with mild atopic dermatitis will be the same.

It is also possible that the dogs skin condition itself is causing it to feel stressed, which leads to further scratching/over grooming making its condition worse, so it is always worth considering stress in your treatment regimen. Our own research showed that dogs with cAD were more likely to over groom themselves, and display ‘problem’ behaviours such as chewing and licking things, hyperactivity, coprophagia (eating poo), begging for and stealing food, attention-seeking, excitability, excessive grooming and reduced trainability [11]. Whilst we cannot know whether itching directly caused these differences, the behaviours worsened with increasing itch severity, and are of a type that are often considered by behavioural biologists to be indicative of stress. So, it is possible that the sensation of constant itching causes them to feel stressed, as it often reported by people with allergic skin conditions. Reducing your dog’s stress could therefore be beneficial even if their problem is caused by allergies.

There are steps you can take to reduce their stress levels. Increased exercise in the form of walks has been shown to help dogs cope with stress [12]. If your dog has experienced a sudden change, such as a house move or a new baby in the house, try to spend more time with them and comfort them to reassure them everything is ok, and re-establish previous routines as best as you can. Pheromone plug-in diffusers, such as Adaptil, are also available, which aim to relieve stress in dogs, these are chemical free and odourless to humans. If you think your dog’s stress is severe, then get in contact with your local certified animal behaviourist who will be able to help identify the cause of the stress and help you to treat it appropriately.

Find your local certified animal behaviourists in the UK

• www.asab.org/ccab-register
• www.apbc.org.uk/help/regions