Allergies, also known as allergic diseases, are a number of 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, a runny nose, shortness of breath, or swelling. Food intolerances and food poisoning are separate conditions.
Allergic rhinitis, also known as hay fever, is a type of inflammation in the nose that occurs when the immune system overreacts to allergens in the air. Signs and symptoms include a runny or stuffy nose, sneezing, red, itchy, and watery eyes, and swelling around the eyes. The fluid from the nose is usually clear. Symptom onset is often within minutes following allergen exposure, and can affect sleep and the ability to work or study. Some people may develop symptoms only during specific times of the year, often as a result of pollen exposure. Many people with allergic rhinitis also have asthma, allergic conjunctivitis, or atopic dermatitis.
Loratadine, sold under the brand name Claritin among others, is a medication used to treat allergies. This includes allergic rhinitis and hives. It is also available in combination with pseudoephedrine, a decongestant, known as loratadine/pseudoephedrine. It is taken by mouth.
Rhinitis, also known as coryza, is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip.
Fexofenadine, sold under the brand name Allegra among others, is an antihistamine pharmaceutical drug used in the treatment of allergy symptoms, such as hay fever and urticaria.
Montelukast, sold under the brand name Singulair among others, is a medication used in the maintenance treatment of asthma. It is generally less preferred for this use than inhaled corticosteroids. It is not useful for acute asthma attacks. Other uses include allergic rhinitis and hives of long duration. For allergic rhinitis it is a second-line treatment.
Nasal congestion is the blockage of nasal breathing usually due to membranes lining the nose becoming swollen from inflamed blood vessels.
Atopy is the tendency to produce an exaggerated immunoglobulin E (IgE) immune response to otherwise harmless substances in the environment. Allergic diseases are clinical manifestations of such inappropriate, atopic responses.
Post-nasal drip (PND), also known as upper airway cough syndrome (UACS), occurs when excessive mucus is produced by the nasal mucosa. The excess mucus accumulates in the back of the nose, and eventually in the throat once it drips down the back of the throat. It can be caused by rhinitis, sinusitis, gastroesophageal reflux disease (GERD), or by a disorder of swallowing. Other causes can be allergy, cold, flu, and side effects from medications.
Levocetirizine, sold under the brand name Xyzal among others, is a third generation antihistamine used for the treatment of allergic rhinitis and long term hives of unclear cause. It is less sedating than older antihistamines. It is taken by mouth.
Rhinorrhea or rhinorrhoea is the free discharge of a thin nasal mucus fluid. The condition, commonly known as a runny nose, occurs relatively frequently. Rhinorrhea is a common symptom of allergies or certain viral infections, such as the common cold. It can be a side effect of crying, exposure to cold temperatures, cocaine abuse, or withdrawal, such as from opioids like methadone. Treatment for rhinorrhea is not usually necessary, but there are a number of medical treatments and preventive techniques available.
Ketotifen, sold under the brand name Zaditor among others, is a second-generation noncompetitive H1-antihistamine and mast cell stabilizer. It is most commonly sold as a salt with fumaric acid, ketotifen fumarate, and is available in two forms. In its ophthalmic form, it is used to treat allergic conjunctivitis. In its oral form, it is used to prevent asthma attacks or anaphylaxis, as well as various mast cell, allergic-type disorders.
Triamcinolone acetonide is a synthetic corticosteroid medication used topically to treat various skin conditions, to relieve the discomfort of mouth sores, and intra-articularly by proceduralists to treat various joint conditions. It is also injected intralesionally to treat inflammation in some parts of the body, particularly the skin. In nasal spray form, it is used to treat allergic rhinitis. It is a more potent derivative of triamcinolone, and is about eight times as potent as prednisone.
Rhinitis medicamentosa is a condition of rebound nasal congestion suspected to be brought on by extended use of topical decongestants and certain oral medications that constrict blood vessels in the lining of the nose although evidence has been contradictory.
Azelastine, sold under the brand name Optivar among others, is a medication primarily used as a nasal spray to treat allergic rhinitis and as eye drops for allergic conjunctivitis. Other uses may include asthma and skin rashes for which it is taken by mouth. Onset of effects is within minutes when used in the eyes and within an hour when used in the nose. Effects last for up to 12 hours.
Mometasone, also known as mometasone furoate, is a steroid medication used to treat certain skin conditions, hay fever, and asthma. Specifically it is used to prevent rather than treat asthma attacks. It can be applied to the skin, inhaled, or used in the nose. Mometasone furoate, not mometasone is used in medical products.
Azatadine (Optimine) is a first-generation antihistamine and anticholinergic that was launched by Schering-Plough in 1973.
Ebastine is a H1 antihistamine with low potential for causing drowsiness.
Laboratory animal allergy (LAA) is an occupational disease of laboratory animal technicians and scientists. It manifests as an allergic response to animal urine, specifically the major urinary proteins (Mups) of rodents, and can lead to the development of asthma. A study of 5641 workers in Japan who were exposed to laboratory animals found 23.1% had one or more allergic symptoms; globally the prevalence among at risk workers is estimated between 11 and 30% According to the National Institutes of Health, prevention of animal allergy depends on the control of allergens in the work environment. This involves a combination of measures to eliminate or control allergen exposure, including engineering controls, administrative controls, and personal protective equipment.
Nonallergic rhinitis is inflammation of the inner part of the nose that is not caused by an allergy. Nonallergic rhinitis involves symptoms including chronic sneezing or having a congested, drippy nose without an identified allergic reaction. Other common terms for nonallergic rhinitis are vasomotor rhinitis and perennial rhinitis. The prevalence of nonallergic rhinitis in otolaryngology is 40%. Allergic rhinitis is more common than nonallergic rhinitis; however, both conditions have similar presentation, manifestation and treatment. Nasal itching and paroxysmal sneezing are usually associated with nonallergic rhinitis in comparison to allergic rhinitis.
