Baclofen is an effective muscle relaxant and antispastic agent with a spinal site of action. Its mode of action is not fully understood. Baclofen inhibits both monosynaptic and polysynaptic reflexes at the spinal level by stimulating the GABAB-receptors, which inhibits the release of glutamate and aspartate. It may also act at intraspinal sites producing CNS depression. Neuromuscular transmission is not affected by Baclofen. Baclofen also exerts an antinoceptive effect but the clinical significance of this is unknown.