1. An agent that causes narrowing of the blood vessel s. SYN: vasoconstrictive (2). 2. A nerve, stimulation of which causes vascular constriction.
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va·so·con·stric·tor .vā-zō-kən-'strik-tər n an agent (as a sympathetic nerve fiber or a drug) that induces or initiates vasoconstriction
vasoconstrictor adj
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n.
an agent that causes narrowing of the blood vessels and therefore a decrease in blood flow. Examples are metaraminol and methoxamine. Vasoconstrictors are used to raise the blood pressure in disorders of the circulation, shock, or severe bleeding and to maintain blood pressure during surgery. Some vasoconstrictors (e.g. phenylephrine, xylometazoline) have a rapid effect when applied to mucous membranes and may be used to relieve nasal congestion. If the blood pressure rises too quickly headache and vomiting may occur. A vasoconstrictor is often added to local anaesthetic solutions used in dentistry to prolong their effectiveness.
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vaso·con·stric·tor (va″zo-) (vas″o-kən-strikґtər) 1. causing constriction of the blood vessels. 2. a motor nerve or chemical compound that causes constriction of the blood vessels.Medical dictionary. 2011.