An allergen is any substance (antigen), most often eaten or inhaled, that is recognized by the immune system and causes an allergic reaction. An antigen is a substance that stimulates an immune response, especially the production of antibodies. ... The immune system is the system of specialized cells and organs that protect an organism from outside biological influences. ... An allergy can refer to several kinds of immune reactions including Type I hypersensitivity in which a persons body is hypersensitised and develops IgE type antibodies to typical proteins. ...

No comprehensive list of allergens is currently possible. Sensitivities vary from one person to another and it is possible to be allergic to an extraordinary range of substances.

Dust, pollen and pet dander are all common allergens, but it is possible to be allergic to anything from chlorine to perfume. Food allergies are not as common as food sensitivity, but some foods such as peanuts (really a legume), nuts, seafood and shellfish are the cause of serious allergies in many people. A few people have even been recorded to be allergic to certain chemicals found in almost all water. Poison ivy (and other plants, like poison sumac or poison oak) is a plant that will cause an allergic reaction for anyone, given enough repeated contact -- like any allergy, the human body must learn to fight the allergen, some bodies learn slower and will appear to be "immune" to poison ivy. After just three years of use dust has blocked this laptop heat sink, making the computer unusable Dust is a general name for minute solid particles with diameter less than 500 micrometers (otherwise see sand or granulates) and, more generally, for finely divided matter. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ... Dander is the excess from the coat or feathers of various animals. ... General Name, Symbol, Number chlorine, Cl, 17 Chemical series halogens Group, Period, Block 17, 3, p Appearance yellowish green Atomic mass 35. ... Perfume is a mixture of fragrant essential oils and aroma compounds, fixatives, and solvents used to give the human body, objects, and living spaces a pleasant smell. ... Food sensitivity or food intolerance is a condition where the individual cannot tolerate certain foodstuffs. ... Binomial name Arachis hypogaea L. The peanut or groundnut (Arachis hypogaea) is a species in the pea family Fabaceae native to South America. ... Hazelnuts from the Common Hazel Chestnut // Botanical definition A nut in botany is a simple dry fruit with one seed (rarely two) in which the ovary wall becomes very hard (stony or woody) at maturity, and where the seed remains unattached or unfused with the ovary wall. ... Spaghetti with seafood (Spaghetti allo scoglio). ... Shellfish is a term used to describe shelled molluscs and crustaceans used as food. ... Water (from the Old English waeter; c. ... Binomial name Toxicodendron radicans (L.) Kuntze Poisonivy (Toxicodendron radicans or Rhus toxicodendron), in the family Anacardiaceae, is a woody vine that is well-known for its ability to produce urushiol, a skin irritant which for most people will cause an agonizing, itching rash. ... Binomial name Toxicodendron vernix Poison Sumac (Toxicodendron vernix or Rhus vernix) is a woody shrub growing to 3 m tall. ... Binomial name Toxicodendron diversilobum Western poison oak (Toxicodendron diversilobum or, previously, Rhus diversiloba) is found only on the Pacific Coast of the United States and of Canada. ...

An allergic reaction can be caused by any form of direct contact with the allergen - eating or drinking a food you are sensitive to (ingestion), breathing in pollen, perfume or pet dander (inhalation), or brushing your body against an allergy-causing plant (direct contact, generally resulting in hives). Other common causes of serious allergy are wasp, fire ant and bee stings, penicillin, and latex. An extremely serious form of an allergic reaction, which can kill in mere minutes, is called anaphylaxis. HIVE can also mean HIVE the Icelandic ISP HIVE is an abstract game programming library. ... Suborder Symphyta Apocrita See text for families. ... The examples and perspective in this article or section may not represent a worldwide view. ... Families Andrenidae Apidae Colletidae Halictidae Megachilidae Melittidae Stenotritidae Bee collecting pollen Bees (Apoidea superfamily) are flying insects, closely related to wasps and ants. ... Penicillin nucleus Penicillin refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... The LaTeX logo, typeset with LaTeX LATEX, written as LaTeX in plain text, is a document preparation system for the TeX typesetting program. ... In medicine, anaphylaxis is a severe and rapid systemic allergic reaction. ...

Common allergens

SEM of miscellaneous plant pollens. Pollens are very common allergens.

The house dust mite, its feces and chitin are common allergens around the home

In addition to foreign proteins found in foreign serum (from blood transfusions) and vaccines, common allergens include: Download high resolution version (1228x935, 215 KB)Source and public domain notice at [1] Pollen from a variety of common plants: sunflower (Helianthus annuus), morning glory Ipomea purpurea, hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose (Oenothera fruticosa) and castor bean (Ricinus communis). ... Download high resolution version (1228x935, 215 KB)Source and public domain notice at [1] Pollen from a variety of common plants: sunflower (Helianthus annuus), morning glory Ipomea purpurea, hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose (Oenothera fruticosa) and castor bean (Ricinus communis). ... Low temperature SEM magnification series for a snow crystal. ... House Dust Mite (Dermatophagoides pteronyssinus) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... House Dust Mite (Dermatophagoides pteronyssinus) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Binomial name Dermatophagoides pteronyssinus The house dust mite (Dermatophagoides pteronyssinus), sometimes abbreviated by allergists to HDM, is a cosmopolitan guest in human habitation. ... Structure of chitin molecule Chitin (IPA: ) is one of the main components in the cell walls of fungi, the exoskeletons of insects and other arthropods, and in some other animals. ... Blood transfusion is the taking of blood or blood-based products from one individual and inserting them into the circulatory system of another. ... A vaccine is an antigenic preparation used to produce active immunity to a disease, in order to prevent or ameliorate the effects of infection by any natural or wild strain of the organism. ...

• Airborne particles (hay fever)
  • grass
  • weed
  • timothy grass
  • birch trees
  • Mold spores
• Drugs
  • penicillin
  • sulfonamides
  • salicylates (also found naturally in numerous fruits)
  • local anaesthetics
• Foods (food allergy)
  • nuts
  • sesame
  • seafood
  • egg (typically albumen, the white)
  • peas, beans, peanuts, soybeans and other legumes
  • soy
  • milk
  • wheat
  • corn or maize
• Insect stings
  • bee sting venom
  • wasp sting venom
• Animal products (animal allergy)
  • Animal hair and dander
  • cockroach calyx
  • dust mite excretion

Seasonal allergic rhinitis, also called pollinosis, hay fever or nasal allergies, and often also written together as hayfever, is a collection of symptoms, predominantly in the nose and eyes, that occur after exposure to airborne particles of dust, dander, or the pollens of certain seasonal plants in people who are... An area of grass-like plants Grass generally describes a monocotyledonous green plant characterized by slender leaves, called blades, which usually grow arching upwards from the ground. ... A weed is an unwanted plant. ... Binomial name Phleum pratense L. Timothy-grass, a North American name for Phleum pratense, is an abundant perennial grass native to most of Europe except for the Mediterranean. ... Species Many species; see text and classification Birch is the name of any tree of the genus Betula, in the family Betulaceae, closely related to the beech/oak family, Fagaceae. ... Moldy Bread Molds, or mould, are various fungi that cover surfaces in the form of fluffy mycelia and usually produce masses of spores (most commonly asexual spores but sometimes sexual). ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Many drugs are provided in tablet form. ... Penicillin nucleus Penicillin refers to a group of β-lactam antibiotics used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms. ... Sulfonamides, also known as sulfa drugs, are synthetic antimicrobial agents derived from sulfonic acid. ... Salicylic acid is a colorless, crystalline organic carboxylic acid. ... Fruit stall in Barcelona, Catalonia. ... A local anesthetic is a drug that reversibly inhibits the propagation of signals along nerves. ... In medicine, food allergy is hypersensitivity to dietary substances, leading to various types of gastrointestinal complaints. ... Binomial name Sesamum indicum L. Sesame (Sesamum indicum) is a flowering plant in the genus Sesamum. ... Spaghetti with seafood (Spaghetti allo scoglio). ... A carton of free-range chicken eggs Ostrich egg Bird eggs are a common food source. ... Albumen redirects here. ... Binomial name Pisum sativum L. A pea is the small, edible round green bean which grows in a pod on the leguminous vine Pisum sativum. ... Green beans Bean is a common name for large plant seeds of several genera of Fabaceae (formerly Leguminosae) used for food or feed. ... Binomial name Arachis hypogaea L. The peanut or groundnut (Arachis hypogaea) is a species in the pea family Fabaceae native to South America. ... Binomial name Glycine max (L.) Merr. ... Varieties of soybean seeds, a popular legume Pea pods The term legume has two closely related meanings in botany, a situation encountered with many botanical common names of useful plants, whereby an applied name can refer to either the plant itself, or to the edible fruit (or useful part). ... Binomial name Glycine max Soybeans (US) or soya beans (UK) (Glycine max) are a high-protein legume (Family Fabaceae) grown as food for both humans and livestock. ... A glass of cow milk Milk most often means the nutrient fluid produced by the mammary glands of female mammals. ... Species T. boeoticum T. compactum T. dicoccoides T. dicoccon T. durum T. monococcum T. spelta T. sphaerococcum References:   ITIS 42236 2002-09-22 Wheat (Triticum spp. ... Binomial name Zea mays L. Maize (Zea mays ssp. ... Binomial name Zea mays L. Maize (Zea mays ssp. ... Classes & Orders See taxonomy Insects are invertebrate animals of the Class Insecta, the largest and (on land) most widely-distributed taxon within the phylum Arthropoda. ... Families Andrenidae Apidae Colletidae Halictidae Megachilidae Melittidae Stenotritidae Bee collecting pollen Bees (Apoidea superfamily) are flying insects, closely related to wasps and ants. ... It has been suggested that Snake poison be merged into this article or section. ... Suborder Symphyta Apocrita See text for families. ... A dogs fur usually consists of longer, stiffer, guard hairs—which can be straight, wiry, or wavy, and of various lengths, hiding a soft, short-haired undercoat. ... Dander is the excess from the coat or feathers of various animals. ... Families Blaberidae Blattellidae Blattidae Cryptocercidae Polyphagidae Nocticolidae Cockroaches are insects of the order Blattodea (the name Blattaria is sometimes used). ... Binomial name Dermatophagoides pteronyssinus The house dust mite (Dermatophagoides pteronyssinus), sometimes abbreviated by allergists to HDM, is a cosmopolitan guest in human habitation. ...

See also

• Allergy
• Hypoallergenic
• Toxin
• Hay fever
• Asthma
• Astelin