Adrenaline increases the "alertness" of the nervous system, meaning it's ready to trigger muscle contraction. It also increases the amount of blood flow and changes the tension of the muscles, which, ...

Infectious agents can cause muscle twitching and spasms, too. The most commonly known is probably tetanus, which causes a phenomenon called lockjaw, where the neck and jaw muscles contract to the ...

Muscle relaxers help reduce muscle stiffness and pain from conditions like cerebral palsy and lower back pain. There are two main types of muscle relaxers: antispastics and antispasmodics. Muscle ...

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