Spasticity and drug therapy

Area of Science:

• Neurology
• Pharmacology

Background:

• Spasticity results from an imbalance of excitatory and inhibitory neurotransmitters in the central nervous system, with largely unknown underlying mechanisms.
• Effective management requires clear classification of spasticity, which encompasses diverse motor control disorders, including cerebral palsy.

Purpose of the Study:

• To provide an overview of the pathophysiology, classification, measurement, and treatment of spasticity.
• To evaluate the established roles and limitations of dantrolene and baclofen in managing spastic disorders.

Main Methods:

• Review of existing literature on spasticity pathophysiology and treatment.
• Analysis of the mechanisms of action, efficacy, and safety profiles of dantrolene and baclofen.
• Discussion of challenges in spasticity measurement and classification.

Main Results:

• Dantrolene and baclofen are recognized treatments for spasticity, but a definitive preference between them is not established.
• Tizanidine's therapeutic role remains undetermined.
• Dantrolene, a direct muscle relaxant, requires caution in patients with liver damage; its metabolism is not fully understood.
• Baclofen, a GABA-B agonist, is a centrally acting muscle relaxant; dose adjustments are necessary for renal impairment, and abrupt withdrawal can cause adverse effects.

Conclusions:

• Dantrolene and baclofen are mainstays in spasticity treatment, though clinical preference is difficult to ascertain.
• Further investigation into the active R(-)-enantiomer of baclofen necessitates reappraisal of existing pharmacokinetic data for the racemate.