- Something that relaxes, relieves, reduces tension. For example, a muscle relaxant is often administered during abdominal surgery to relax the diaphragm and keep it from moving during the surgery.
* * *1. Relaxing; causing relaxation; reducing tension, especially muscular tension. 2. An agent that reduces muscular tension or produces skeletal muscle paralysis, usually referred to as a muscle r..- depolarizing r. an agent, e.g., succinylcholine, that induces depolarization of the motor endplate and so paralyzes skeletal muscle by a phase I block.- muscle r. a drug with the capacity to reduce muscle tone; may be either a peripherally acting muscle r. such as curare and act to produce blockade at the neuromuscular junction (and thus useful in surgery), or act as a centrally acting muscle r. exerting its effects within the brain and spinal cord to diminish muscle tone (and thus useful in muscle spasm or spasticity).- neuromuscular r. an agent, e.g., curare or succinylcholine, that produces relaxation of striated muscle by interruption of transmission of nervous impulses at the myoneural junction.- nondepolarizing r. an agent, e.g., tubocurarine, that paralyzes skeletal muscle without depolarization of the motor endplate, as in phase II block.- smooth muscle r. an agent, such as an antispasmodic, bronchodilator, or vasodilator, that reduces the tension or tone of smooth (involuntary) muscle.
* * *re·lax·ant ri-'lak-sənt adj of, relating to, or producing relaxation <an anesthetic and \relaxant agent>relaxant n a substance (as a drug) that relaxes specif one that relieves muscular tension
* * *n.
* * *re·lax·ant (re-lakґsənt) [L. relaxare to loosen] 1. lessening or reducing tension. 2. an agent that lessens tension.
Medical dictionary. 2011.