Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include red eyes, an itchy rash, sneezing, coughing, a runny nose, shortness of breath, or swelling. Note that food intolerances and food poisoning are separate conditions.
An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response.
A food allergy is an abnormal immune response to food. The symptoms of the allergic reaction may range from mild to severe. They may include itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressure. This typically occurs within minutes to several hours of exposure. When the symptoms are severe, it is known as anaphylaxis. A food intolerance and food poisoning are separate conditions, not due to an immune response.
Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes are not contagious or life-threatening, but can be very uncomfortable.
Skin disorders are among the most common health problems in dogs, and have many causes. The condition of a dog's skin and coat is also an important indicator of its general health. Skin disorders of dogs vary from acute, self-limiting problems to chronic or long-lasting problems requiring life-time treatment. Skin disorders may be primary or secondary in nature, making diagnosis complicated.
Allergic contact dermatitis (ACD) is a form of contact dermatitis that is the manifestation of an allergic response caused by contact with a substance; the other type being irritant contact dermatitis (ICD).
Allergies to cats, a type of animal allergy, are one of the most common allergies experienced by humans. Among the eight known cat allergens, the most prominent allergen is secretoglobin Fel d 1, which is produced in the anal glands, salivary glands, and, mainly, in sebaceous glands of cats, and is ubiquitous in the United States, even in households without cats. The second most common is Fel d 2, this type is triggered by the cats dead skin flakes (dander) that are floating in the air as well as in the smell of cat urine.
Egg allergy is an immune hypersensitivity to proteins found in chicken eggs, and possibly goose, duck, or turkey eggs. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus.
Flea allergy dermatitis is an eczematous itchy skin disease of dogs and cats. For both of these domestic species, flea allergy dermatitis is the most common cause of skin disease. Affected animals develop allergic reactions to chemicals in flea saliva. Symptoms of this reaction include erythema (redness), papules (bumps), pustules, and crusts (scabs). If severe, hair loss will occur in the affected area. Dogs with flea allergy dermatitis often show hair loss and eczematous skin rash on the lower back, upper tail, neck, and down the back of the legs. Cats with flea allergy dermatitis may develop a variety of skin problems, including feline eosinophilic granuloma, miliary dermatitis, or self-inflicted alopecia from excessive grooming.
Skin allergy testing comprises a range of methods for medical diagnosis of allergies that attempts to provoke a small, controlled, allergic response.
An allergic response is a hypersensitive immune reaction to a substance that normally is harmless or would not cause an immune response in everyone. An allergic response may cause harmful symptoms such as itching or inflammation or tissue injury.
Eyelid dermatitis is commonly related to atopic dermatitis or allergic contact dermatitis. Volatile substances, tosylamide, epoxy hardeners, insect sprays, and lemon peel oil may be implicated, with many cases of eyelid contact dermatitis being caused by substances transferred by the hands to the eyelids.
Oclacitinib, sold under the brand name Apoquel among others, is a veterinary medication used in the control of atopic dermatitis and pruritus from allergic dermatitis in dogs at least 12 months of age. Chemically, it is a synthetic cyclohexylamino pyrrolopyrimidine janus kinase inhibitor that is relatively selective for JAK1. It inhibits signal transduction when the JAK is activated and thus helps downregulate expression of inflammatory cytokines.
Allergies in children, an incidence which has increased over the last fifty years, are overreactions of the immune system often caused by foreign substances or genetics that may present themselves in different ways. There are multiple forms of testing, prevention, management, and treatment available if an allergy is present in a child. In some cases, it is possible for children to outgrow their allergies.
Cats exposed to allergens may develop allergies or allergic reactions. Allergies tend to become evident and intensify over extended periods of time and can take years to develop. Some allergic diseases and allergies in cats include feline atopic dermatitis, flea allergy dermatitis, feline-mosquito hypersensitivity, and food-induced allergy. In the case of feline atopy, hypersensitivity to allergens is due to genetic predisposition. However, various allergies may arise due to environmental factors. Allergens, ingested, inhaled, or airborne, can be seasonal or non-seasonal, similar to allergies in humans. Suspected seasonal allergens include but are not limited to pollen, fleas, and mosquito bites; suspected non-seasonal allergens include but are not limited to plastic materials, food, dust, trees, and grass. After exposure to suspected allergens, symptoms may be immediate or delayed, arising within a few minutes to two hours. Symptoms can include both dermatological and gastrointestinal signs such as itchy skin, hair loss and excessive scratching. In cases of feline atopic dermatitis or atopy in cats, pruritic skin diseases may result; however, signs can also include miliary dermatitis, symmetrical alopecia, and lesions of the eosinophilic granuloma complex.
Hypoallergenic dog food diets are created for dogs that experience food-related allergies causing adverse effects to their physical health.Super Hypoallergenic is enzymatic hydrolyzed hypoallergenic ostrich protein. The molecules that usually become allergens are intact proteins or glycoproteins. Hypoallergenic dog food diets offer a variety of protein sources that are unique by using proteins that are not recognized by the dog's antibodies as being antigens, minimizing allergic reactions for example Ostrich meat, bones and sinews. Adding novel protein sources, such as novel meats that a dog or its ancestors have never been exposed to is one method. Novel proteins can also be created by chemically modifying well known protein sources using hydrolysis techniques, rendering proteins unrecognizable by the gastrointestinal tract. Not all antigens are specific to proteins, however, and it is possible for anything that the body ingests to become an allergen. Providing diets with a limited amount of ingredients can be used for diagnostic purposes, as well as for dogs who are allergic to the common ingredients that are used in pet food. Certain nutrients are commonly incorporated into hypoallergenic dog food to help alleviate the symptoms of an allergic reaction. These ingredients include omega-3 fatty acids, Vitamins A and E, zinc, novel carbohydrates, and fiber.
Fish allergy is an immune hypersensitivity to proteins found in fish. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus. Fish is one of the eight common food allergens which are responsible for 90% of allergic reactions to foods: cow's milk, eggs, wheat, shellfish, peanuts, tree nuts, fish, and soy beans.
Shellfish allergy is among the most common food allergies. "Shellfish" is a colloquial and fisheries term for aquatic invertebrates used as food, including various species of molluscs such as clams, mussels, oysters and scallops, crustaceans such as shrimp, lobsters and crabs, and cephalopods such as squid and octopus. Shellfish allergy is an immune hypersensitivity to proteins found in shellfish. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus. Shellfish is one of the eight common food allergens, responsible for 90% of allergic reactions to foods: cow's milk, eggs, wheat, shellfish, peanuts, tree nuts, fish, and soy beans.
Metal allergies inflame the skin after it has been in contact with metal. They are a form of allergic contact dermatitis. They are becoming more common, as of 2021, except in areas with regulatory countermeasures.
Anti-allergic agents are medications used to treat allergic reactions. Anti-allergic agents have existed since 3000 B.C in countries such as China and Egypt. It was not until 1933 when antihistamines, the first type of anti-allergic agents, were developed. Common allergic diseases include allergic rhinitis, allergic asthma and atopic dermatitis with varying symptoms, including runny nose, watery eyes, itchiness, coughing, and shortness of breath. More than one-third of the world's population is currently being affected by one or more allergic conditions.
