ATC Group: M03B Muscle relaxants, centrally acting agents

Baclofen depresses monosynaptic and polysynaptic reflex transmission, probably by stimulating the GABA_B-receptors. This stimulation in turn inhibits the release of the excitatory amino acids glutamate and aspartate. Neuromuscular transmission is unaffected by baclofen. Baclofen also exerts an antinociceptive effect.

Carisoprodol is a centrally acting skeletal muscle relaxant whose mechanism of action is not completely understood but may be related to its sedative actions. Carisoprodol is indicated for the relief of discomfort associated with acute, painful musculoskeletal conditions in adults. Most common adverse reactions (incidence > 2%) are drowsiness, dizziness, and headache. Carisoprodol might be mixtured with Aspirin and Codeine Phosphate.

Chlorzoxazone is a centrally-acting agent for painful musculoskeletal conditions. Data available from animal experiments as well as human study indicate that chlorzoxazone acts primarily at the level of the spinal cord and subcortical areas of the brain where it inhibits multisynaptic reflex arcs involved in producing and maintaining skeletal muscle spasm of varied etiology.

Cyclobenzaprine relieves skeletal muscle spasm of local origin without interfering with muscle function. Cyclobenzaprine has not been shown to be effective in muscle spasm due to central nervous system disease.

Eperisone is an antispastic agent used for treatment of diseases characterized by muscle stiffness and pain.

Methocarbamol is a centrally acting muscle relaxant. Its muscle relaxing action is the result of the inhibition of polysynaptic reflexes in the spinal marrow and subcortical centres.

Orphenadrine, which is a congener of diphenhydramine without sharing its soporific effect, is an anti-muscarinic agent. Orphenadrine is used as the hydrochloride in the symptomatic treatment of Parkinsonism.

Pridinol is a piperidin- polyalcohol derivative with the chemical formula 1,1-Diphenyl-1-ol-3-piperidin-propan-methanesulfonate. Its pharmacological effect develops via an atropine-like mechanism that acts on both smooth and the striated muscles. This effect is used for the treatment of skeletal muscle tension of both central and peripheral origin.

Thiocolchicoside is a semisynthetic sulphide derivative of colchicoside, showing muscle relaxant pharmacological activity. In vitro thiocolchicoside binds solely with gaba receptors and glycinergic stricnine sensitive.Tivozanib

Tizanidine is a centrally acting skeletal muscle relaxant. Polysynaptic signal transmission at spinal interneuron level, which is responsible for excessive muscle tone, is inhibited and muscle tone reduced.

As a skeletal muscle relaxant whose prototype is mephenesine, tolperisone induces ataxia and muscle weakness in animal models by acting on the central nervous system at the spinal level. In fact it inhibits polysynaptic and monosynaptic reflexes with little action on non-reflex muscle response and without potentiating the phenobarbital sleep.