The slow-reacting substance of anaphylaxis or SRS-A is a mixture of the leukotrienes LTC4, LTD4 and LTE4. Mast cells secrete it during the anaphylactic reaction, inducing inflammation. [1] It can be found in basophils.
Leukotrienes are a family of eicosanoid inflammatory mediators produced in leukocytes by the oxidation of arachidonic acid (AA) and the essential fatty acid eicosapentaenoic acid (EPA) by the enzyme arachidonate 5-lipoxygenase.
Inflammation is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair.
It induces prolonged, slow contraction of smooth muscle and has a major bronchoconstrictor role in asthma. [2] Compared to histamine, it is approximately 5000 times more potent and has a slower onset but longer duration of action.[ citation needed ]
Bronchoconstriction is the constriction of the airways in the lungs due to the tightening of surrounding smooth muscle, with consequent coughing, wheezing, and shortness of breath.
Asthma is a common long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include episodes of wheezing, coughing, chest tightness, and shortness of breath. These may occur a few times a day or a few times per week. Depending on the person, they may become worse at night or with exercise.
Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death. It typically causes more than one of the following: an itchy rash, throat or tongue swelling, shortness of breath, vomiting, lightheadedness, and low blood pressure. These symptoms typically come on over minutes to hours.
Diazepam, first marketed as Valium, is a medicine of the benzodiazepine family that typically produces a calming effect. It is commonly used to treat a range of conditions including anxiety, alcohol withdrawal syndrome, benzodiazepine withdrawal syndrome, muscle spasms, seizures, trouble sleeping, and restless legs syndrome. It may also be used to cause memory loss during certain medical procedures. It can be taken by mouth, inserted into the rectum, injected into muscle, or injected into a vein. When given into a vein, effects begin in one to five minutes and last up to an hour. By mouth, effects may take 40 minutes to begin.
Acetylcysteine, also known as N-acetylcysteine (NAC), is a medication that is used to treat paracetamol (acetaminophen) overdose, and to loosen thick mucus in individuals with cystic fibrosis or chronic obstructive pulmonary disease. It can be taken intravenously, by mouth, or inhaled as a mist. Some people use it as a dietary supplement.
Antivenom, also known as antivenin, venom antiserum and antivenom immunoglobulin, is a medication made from antibodies which is used to treat certain venomous bites and stings. They are recommended only if there is significant toxicity or a high risk of toxicity. The specific antivenom needed depends on the species involved. It is given by injection.
Royal jelly is a honey bee secretion that is used in the nutrition of larvae, as well as adult queens. It is secreted from the glands in the hypopharynx of nurse bees, and fed to all larvae in the colony, regardless of sex or caste.
Matricaria chamomilla, commonly known as chamomile, Italian camomilla, German chamomile, Hungarian chamomile (kamilla), wild chamomile or scented mayweed, is an annual plant of the composite family Asteraceae. M. chamomilla is the most popular source of the herbal product chamomile, although other species are also used as chamomile.
The incidence of life-threatening hypersensitivity reactions occurring during surgery and anaesthesia is around one in 10,000 procedures. Serious allergic reactions to anesthetic medications are rare and a usually attributable to factors other than the anesthetic. Neuromuscular blocking agents, natural rubber latex, and antibiotics are the most common causes of serious allergic reactions during surgery. The mortality rate from these reactions ranges between 3-9%.
Butalbital is a barbiturate with an intermediate duration of action. Butalbital is often combined with other medications, such as paracetamol (acetaminophen) or aspirin, for the treatment of pain and headache. The various formulations combined with codeine are FDA-approved for the treatment of tension headaches. Butalbital has the same chemical formula as talbutal but a different structure—one that presents as 5-allyl-5-isobutylbarbituric acid. Its use for headaches is discouraged due to its toxicity and the availability of safer agents.
Metamizole or dipyrone, is a painkiller, spasm reliever and fever reliever. Like paracetamol, it has minimal anti-inflammatory effects. It is most commonly given by mouth or by injection.
Soy allergy is a type of food allergy. It is a hypersensitivity to dietary substances from soy, causing an overreaction of the immune system which may lead to severe physical symptoms for millions of people. The Asthma and Allergy Foundation of America estimates soy is among the eight most common food allergens for pediatric and adult food allergy patients. It is usually treated with an exclusion diet and vigilant avoidance of foods that may be contaminated with soy ingredients. The most severe food allergy reaction is called anaphylaxis and is a medical emergency requiring immediate attention and treatment with epinephrine.
Milk allergy is an adverse immune reaction to one or more proteins in cow's milk. When allergy symptoms occur, they can occur rapidly or have a gradual onset. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine among other measures. The latter can take hours to days to appear, with symptoms including atopic dermatitis, inflammation of the esophagus, enteropathy involving the small intestine and proctocolitis involving the rectum and colon.
Pholcodine is a drug which is an opioid cough suppressant (antitussive). It helps suppress unproductive coughs and also has a mild sedative effect, but has little or no analgesic effects. It is also known as morpholinylethylmorphine and homocodeine.
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.
Wheat allergy is an allergy to wheat which typically presents itself as a food allergy, but can also be a contact allergy resulting from occupational exposure. Like all allergies, wheat allergy involves immunoglobulin E and mast cell response. Typically the allergy is limited to the seed storage proteins of wheat. Some reactions are restricted to wheat proteins, while others can react across many varieties of seeds and other plant tissues. Wheat allergy is rare. Prevalence in adults was found to be 0.21% in a 2012 study in Japan.
Skin allergy testing or Skin prick test is a method for medical diagnosis of allergies that attempts to provoke a small, controlled, allergic response.
An antileukotriene, also known as leukotriene modifier and leukotriene receptor antagonist, is a medication which functions as a leukotriene-related enzyme inhibitor or leukotriene receptor antagonist and consequently opposes the function of these inflammatory mediators; leukotrienes are produced by the immune system and serve to promote bronchoconstriction, inflammation, microvascular permeability, and mucus secretion in asthma and COPD. Leukotriene receptor antagonists are sometimes colloquially referred to as leukasts.
A drug allergy is an allergy to a drug, most commonly a medication, and is a form of adverse drug reaction. Medical attention should be sought immediately if an allergic reaction is suspected.
Arachidonate 5-lipoxygenase inhibitors are compounds that slow or stop the action of the arachidonate 5-lipoxygenase enzyme, which is responsible for the production of inflammatory leukotrienes. The overproduction of leukotrienes is a major cause of inflammation in asthma and allergic rhinitis and Osteoarthritis.
Exercise-Induced Anaphylaxis (EIAn) is a rare condition in which anaphylaxis, a serious or life-threatening allergic response, is brought on by physical activity. Approximately 5-15% of all reported cases of anaphylaxis are thought to be exercise-induced.
Medical Subject Headings (MeSH) is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it serves as a thesaurus that facilitates searching. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed article database and by NLM's catalog of book holdings. MeSH is also used by ClinicalTrials.gov registry to classify which diseases are studied by trials registered in ClinicalTrials.
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