Carisoprodol (Soma), Cyclobenzaprine (Flexeril), Metaxalone (Skelaxin), Tizanidine (Zanaflex)
relax muscle spasm and dpress muscle spasticity by enhancing GABA and primarily causing CNS sedation. It has NOT direct effects on skeletal muscle
CNS depression (drowsiness, dizziness, lightheadedness, sleepiness, fatigue). dry mouth, blurred vision, photophobia, urinary retention, and constipation.
Hepatic toxicity (anorexia, nausea, vomiting, abdominal pain, jaundice) and physical dependence, life threatening abstinence syndrome if abruptly withdrawn.
Suppress hyperactive reflexes by mimicking the inhibitory neurotransmitter, GABA, on spinal neurons (CNS). It is centrally acting drug, having no direct effects on skeletal muscle
GI discomfort(Nausea, constipation), urinary retention, CNS depression (drowsiness, dizziness, lightheadedness, sleepiness, fatigue), weakness.
Abrupt stop can cause withdrawal symptoms: visual hallucinations, paranoid ideation, and seizures.
Diazepam (Valium), benzodiazepine
Acts in the CNS to suppress spasticity by mimicking GABA at receptors in the spinal cord and brain to produce sedation. Does not affect skeletal muscle directly.
CNS depression (drowsiness, dizziness, lightheadedness, sleepiness, fatigue). GI discomfort