Centrally acting muscle relaxants
Carisoprodol (Soma), Cyclobenzaprine (Flexeril) and
Methocarbamol (Robaxin).
These drugs decrease pain, increase range of motion and have a sedative effect on
the patient. Centrally acting muscle relaxants should not be taken concurrently with
central nervous system depressants such as barbiturates, narcotics, and alcohol.Diazepam (Valium) and Baclofen (Lioresal)
These are used to treat acute spasms from muscle trauma and for treating spasms
caused by chronic neurologic disorders.Dantrolene sodium (Dantrium)
This is a peripherally acting muscle relaxant. Peripherally acting muscle relax-
ants depress neuron activity at the skeletal muscles and have a minimal effect on
the central nervous system. These are most effective for spasticity or muscle
contractions caused by chronic neurologic disorders. This is also used to treat
malignant hypertension which is an allergic reaction to anesthesia.MYASTHENIA GRAVIS
Myasthenia gravis is a disease where nerve impulses don’t reach the nerves in
muscle endings (myoneural junction) because of an inadequate secretion of or
loss of acetylcholine due to action of acetylcholinesterase, an enzyme that
destroysacetylcholine at the myoneural junction.
Patients experience fatigue and muscle weakness—particularly in respiratory
muscles, facial muscles, and muscles in the extremities. They have drooping eye-
lids (ptosis) and difficulty in chewing and swallowing and their respiratory mus-
cles become paralyzed which leads to respiratory arrest. Acetylcholinesterase
(ACE inhibitors) are used to treat the symptoms of this disease. They include
ambenonium (Mytelase), edrophonium Cl (Tensilon), Neostigmine bromide
(Prostigmin), and Pyridostigmine bromide (Mestinon).MULTIPLE SCLEROSIS
Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous
system. Multiple lesions of the myelin sheath that surround the nerve fibers
occur that are called plaque. Myelin enables nerves to conduct impulses.(^290) CHAPTER 15 Nervous System Drugs