<P> A muscle relaxant is a drug that affects skeletal muscle function and decreases the muscle tone . It may be used to alleviate symptoms such as muscle spasms , pain , and hyperreflexia . The term `` muscle relaxant '' is used to refer to two major therapeutic groups : neuromuscular blockers and spasmolytics . Neuromuscular blockers act by interfering with transmission at the neuromuscular end plate and have no central nervous system ( CNS ) activity . They are often used during surgical procedures and in intensive care and emergency medicine to cause temporary paralysis . Spasmolytics , also known as `` centrally acting '' muscle relaxants , are used to alleviate musculoskeletal pain and spasms and to reduce spasticity in a variety of neurological conditions . While both neuromuscular blockers and spasmolytics are often grouped together as muscle relaxants , the term is commonly used to refer to spasmolytics only . </P>
when are centrally acting skeletal muscle relaxants used
to alleviate musculoskeletal pain and spasms to reduce spasticity in a variety of neurological conditions