Baclofen Indications
Baclofen is primarily indicated for the alleviation of signs and symptoms of spasticity resulting from multiple sclerosis, particularly for the relief of flexor spasms, concomitant pain, clonus, and muscular rigidity in patients with reversible spasticity to aid in restoring residual function. 1
Primary FDA-Approved Indications
- Spasticity resulting from multiple sclerosis
- Spinal cord injuries and other spinal cord diseases
Mechanism and Specific Uses
Baclofen is a GABA-B receptor agonist that functions as a centrally acting muscle relaxant. It works by:
- Inhibiting both monosynaptic and polysynaptic reflexes at the spinal level
- Reducing transmission of excitatory signals that maintain muscle tone
- Decreasing the frequency and severity of muscle spasms
Clinical Applications
Recommended Uses:
- Multiple sclerosis-related spasticity: First-line for generalized spasticity (30-80 mg/day in divided doses) 2
- Spinal cord injury spasticity: Effective for reducing muscle tone and painful spasms 3
- Severe spasticity unresponsive to oral medications: Intrathecal baclofen therapy is indicated 4
Not Recommended For:
- Skeletal muscle spasm from rheumatic disorders 1
- Stroke (efficacy not established) 1
- Cerebral palsy (efficacy not established) 1
- Parkinson's disease (efficacy not established) 1
Administration Routes
Oral Administration
- Starting dose: Usually low (5-10 mg three times daily)
- Maintenance: Typically 30-80 mg/day in divided doses
- Should be taken consistently to maintain therapeutic blood levels 2
Intrathecal Administration
- Reserved for severe spasticity unresponsive to maximum doses of oral baclofen, tizanidine, and/or dantrolene 3
- Allows for precise dose titration with programmable pump
- More than 80% of patients show improvement in muscle tone 3
- More than 65% show improvement in spasms 3
Important Considerations
Safety Concerns
- Abrupt discontinuation can cause potentially life-threatening withdrawal symptoms including:
- Visual and auditory hallucinations
- Anxiety, agitation, delirium
- Fever, tremors, tachycardia
- Seizures 5
Perioperative Management
- Should be taken preoperatively including the day of operation to avoid withdrawal 5
- Intrathecal baclofen withdrawal is particularly dangerous and can lead to rhabdomyolysis, multiorgan failure, and death 5
Efficacy Duration
- Long-term studies show baclofen remains effective for years without developing significant tolerance 4
- Most effective when initiated in early stages of disease before major disabilities become permanent 6
Monitoring Parameters
- Regular assessment of sedation level
- Signs of drug accumulation
- Improvement in spasticity using standardized scales
- Renal function (use with caution in renal impairment) 2
Baclofen should be considered a mainstay treatment for spasticity of spinal origin, with careful attention to proper dosing and avoidance of abrupt discontinuation to prevent potentially serious withdrawal complications.