Article By Dr. Stan Kunin In Collaboration With Diana Kunin
Itchy skin is probably one of the most common reasons for an owner to bring their dog into my office. It is frustrating to watch a dog scratch or bite and chew their body all day and night. And it's not just an annoyance to the owner, causing lack of, or interrupted sleep, it can cause damage to the animal's skin and can create sores and infections in the afflicted areas.
There are many causes for itchy skin. Parasites, such as fleas and mites can be the root of the problem. However, other skin problems caused by bacterial and yeast infections can be the culprit.
This article will discuss the most common cause for itchiness, allergies. Heredity can play a role in dog allergies. Certain breeds are very susceptible to allergy related skin issues; such as the Golden Retriever, Wheaton Terrier, West Highland Terrier, English and French Bulldogs, Bichon Frise, etc. Nonetheless, allergies can occur in any breed or mixed breeds.
The definition of an allergy can be a complex one. Basically, an allergy is when the immune system over reacts to a foreign substance causing a series of biochemical events which lead to histamine releases. Histamine then causes an inflammation of the tissue which leads to itching, facial swelling, hives, vomiting, diarrhoea, to mention a few. When humans experience allergies, it usually manifests itself in the respiratory systems such as the nose, sinus, and/or lungs, causing them to suffer from sneezing and coughing attacks. Or it could manifest itself in the eyes and nose making them very itchy. In dogs, allergy symptoms are slightly different, as it typically targets the skin, mainly the feet and the ears.
There are two types of allergies. An immediate type occurs minutes after exposure and causes hives or raised and reddened welts. A severe type of this "immediate" type is called an anaphylactic reaction. Symptoms include, vomiting, diarrhoea, difficulty breathing, and/or swelling of the tongue and throat. It can be dangerous in that if untreated, death can occur.
The other type of allergy is the delayed kind, when the response occurs hours or days later and causes intense itching.
Dog allergies fall into four types:
- Fleas and other biting insects: Flea bite allergies are a good example of the delayed hypersensitivity reaction, and occurs when the body reacts to the flea's saliva hours after the flea has gone away. The best way to minimize this kind of allergy is to use a topical or oral flea medication. There are many flea control solutions such as Frontline, Advantage, and Revolution. Talk to your veterinarian and find out which he/she recommends.
- Inhaled allergy: This is also called atopy. Atopy comes from inhaling pollens from trees, weeds, and other wind-borne substances, or from dust mites, molds, etc. To find out exactly what the dog is reacting to, a skin test can be performed to determine which allergen is causing the problem and only then can a hypo-sensitization injection be administered. These injections may work, but the owner would need to inject their dog weekly for up to a year, and may provide inconsistent results. Medications, such as antihistamines or a cortisone treatments can produce some relief. Also, an oatmeal shampoo can help soothe the skin.
- Food and drug allergy: Some dogs aren't capable of handling certain proteins like beef, chicken, or lamb. Diagnosing food allergies can prove very challenging and the treatment can be unrewarding. One has to experiment with different protein sources such as fish and potato, or rabbit and pea, etc. to find out if the dog reacts or not. Sometime a prescription diet called Z/D, which can be acquired from a veterinary clinic, can be helpful. Z/D is made up of hydrolyzed protein which means that the protein molecule has been manufactured in minute amount so the body doesn't recognize it as being foreign. Drug allergies, as from penicillin or other antibiotics can cause hives and facial swelling. The avoidance of these drugs will help to prevent future problems.
- Contact allergy: Grass allergies are common and can occur when a dog lies on the grass on their belly. This is because there is less hair on the belly than on other parts of their body, and the skin has greater contact with the allergen. Another contact allergy concern can arise from plastic food or water bowls. If allergic, a dog will have a reaction around their mouth or muzzle. Switching to metal or ceramic bowls will help. Sometimes, even certain shampoos can cause an allergic reaction. Rarely, a topical flea medication can cause an allergy. When this happens, it is best to bathe them in an oatmeal based shampoo as soon as possible.
There are many treatments for allergies. If you know the source (food, flea, grass, drugs, etc), allergic reactions can be minimized simply by avoiding the substance(s) causing the reaction. Some dogs will respond to an over-the-counter antihistamines such as Benedryl. However, there are dogs that may require a prescription drug which entail a trip to the pharmacy. Antihistamines do not always work for all dogs, keeping in mind that sometimes it can take a few days before the owner will see it's effect.
Cortisone can help many dogs with allergies. However, cortisone does come with potential side effects, such as drinking and urinating excessively, increased appetite, and rarely, lethargy, hyperactivity, and/or irritability. Cortisone treatments must be used with constant veterinary supervision as it can lead to long term problems, especially to the organs, such as the liver. Cortisone can be a very effective treatment and is safe so as long as it's done with continuous veterinary supervision. There are dogs that may need cortisone treatments for life. By getting the blood tested periodically, you can help minimize any liver or other organ damage. There are different types of cortisones, and by working with your veterinarian, you can find the lowest dose and the proper frequency for medicating your dog in order to provide the safest results.
Cyclosporine (Atopica) is another drug than can be helpful. This drug is expensive and can also produce some side effects, such as vomiting. Sometimes, even an anti-anxiety drug can help decrease the symptoms caused by the over reaction to an allergen. Your veterinarian may refer you to a board certified veterinary dermatologist who can help find the right drug or combination thereof to resolve the frustrations caused by an itchy dog.
Always talk to your veterinarian and ask him/her questions. There are many options available to dog owners, but patience is key to discovering the best way to give relief to your allergic dog.
About Dr. Stan Kunin
Stan Kunin DVM graduated from UC Davis in 1978 and has had his own practice in Woodland Hills, California since 1986. Dr. Kunin is a special veterinarian who was born 80% deaf, but the weakness in his hearing has helped to give him a 6th sense about animal care and the wellbeing of his patients.
In a regular series of articles for the Jason Debus Heigl Foundation, Dr. Kunin shares his thoughts, opinions and advice on animal matters.