alpha-blocker

al·pha-block·er

(ăl′fə-blŏk′ər)n. A drug that blocks or counteracts the effects of epinephrine and other molecules that stimulate alpha-receptors, leading to various physiological reactions such as vasodilation and a decrease in blood pressure. Also called alpha-adrenergic antagonist, alpha-adrenergic blocker.

alpha-blocker

n (Pharmacology) any of a class of drugs that prevent the stimulation of alpha adrenoceptors, a type of receptor in the sympathetic nervous system, by adrenaline and noradrenaline and that therefore cause widening of blood vessels: used in the treatment of high blood pressure and prostatic hyperplasia

Thesaurus

Noun

alpha-blocker - any of various drugs that block alpha-adrenergic receptors; used in treating benign prostatic hyperplasia; relaxes the muscles of the prostate and bladderalpha blocker, alpha-adrenergic blocker, alpha-adrenergic blocking agentblocking agent, blocker - a class of drugs that inhibit (block) some biological processMinipress, prazosin - antihypertensive drug (trade name Minipress)Hytrin, terazosin - antihypertensive drug (trade name Hytrin) used to treat high blood pressure

alpha-blocker

alpha

[al´fah] the first letter of the Greek alphabet, α; used to denote the first position in a classification system; as, in names of chemical compounds, to distinguish the first in a series of isomers, or to indicate the position of substituent atoms or groups; also used to distinguish types of radioactive decay, brain waves or rhythms, adrenergic receptors, and secretory cells that stain with acid dyes, such as the alpha cells of the pancreas.alpha-adrenergic blocking agent (alpha-blocker) (alpha-blocking agent) any of a group of drugs that selectively inhibit the activity of receptors" >alpha receptors in the sympathetic nervous system. As with beta-adrenergic blocking agents" >beta-adrenergic blocking agents, alpha-blocking agents compete with the catecholamines" >catecholamines at peripheral autonomic receptor sites. This group includes ergot" >ergot and its derivatives, and phentolamine" >phentolamine.alpha chain disease the most common heavy chain disease, occurring predominantly in young adults in the Mediterranean area, and characterized by plasma cell infiltration of the lamina propria of the small intestine resulting in malabsorption with diarrhea, abdominal pain, and weight loss, or, exceedingly rarely, by pulmonary involvement. The gastrointestinal form is immunoproliferative small intestine disease.alpha-fetoprotein (AFP) a plasma protein produced by the fetal liver, yolk sac, and gastrointestinal tract and also by carcinoma" >hepatocellular carcinoma, germ cell neoplasms, and other cancers in adults; elevated levels may also be seen in benign liver disease such as cirrhosis and viral hepatitis. The serum AFP level is used to monitor the effectiveness of cancer treatment.
During pregnancy some AFP crosses from the amniotic fluid to the mother's blood. If the fetus has a neural tube defect, large amounts of AFP will be found in the amniotic fluid and maternal blood. Blood screening tests for serum AFP can thus be done as a first step in the screening process; if test results are positive, further testing is indicated to diagnose the defect.alpha particles a type of emission produced by the disintegration of a radioactive substance. The atoms of radioactive elements such as uranium and radium are very unstable, continuously breaking apart with explosive violence and emitting particulate and nonparticulate types of radiation. The alpha particles, consisting of two protons and two neutrons, have an electrical charge and form streams of tremendous energy when they are released from the disintegrating atoms. These streams of energy (rays" >alpha rays) can be used in treatment of various malignancies. See also radiation and radiation therapy.

α-ad·re·ner·gic block·ing a·gent

a class of drugs that competes with α-adrenergic agonists for available receptor sites; some compete for both α₁ and α₂ receptors (for example, phentolamine, phenoxybenzamine hydrochloride), whereas others are primarily either α₁ (for example, prazosin, terazosin) or α₂ receptor blocking agents (for example, yohimbine). Synonym(s): α-adrenoceptor antagonist, alpha-blocker

alpha-blocker

alpha-adrenergic antagonist

An adrenergic blocking agent which produces miosis and a slight reduction in intraocular pressure. It is used mainly to reverse the mydriatic effect of sympathomimetic drugs (e.g. phenylephrine hydrochloride), or even some antimuscarinic drugs (e.g. tropicamide). Common agents include dapiprazole and moxisylyte (thymoxamine). Syn. alpha-blocker. See sympatholytic drugs.

alpha-blocker

al·pha-block·er

alpha-blocker

alpha-blocker

alpha

α-ad·re·ner·gic block·ing a·gent

alpha-blocker

alpha-adrenergic antagonist

alpha-blocker

Synonyms for alpha-blocker

noun any of various drugs that block alpha-adrenergic receptors

Synonyms

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