Muscle Relaxants for Multiple Sclerosis Patients
Baclofen is the preferred muscle relaxant for patients with Multiple Sclerosis (MS) due to its established efficacy in treating spasticity resulting from MS, particularly for relief of flexor spasms, concomitant pain, clonus, and muscular rigidity. 1, 2
First-Line Treatment Option
- Baclofen is specifically indicated for the alleviation of signs and symptoms of spasticity resulting from multiple sclerosis, with particular effectiveness for relieving flexor spasms, pain, clonus, and muscular rigidity 1
- Baclofen works by acting as a GABA-B receptor agonist, which helps reduce muscle tone and spasticity in MS patients 2
- Studies have shown baclofen provides statistically significant reduction in frequency of spasms and clonus, with improved range of joint movement, enabling patients to maintain functional status for prolonged periods 2
- Optimum effect is achieved when baclofen is administered in the early stages of disease, before major disabilities become permanent 2
Dosing Considerations
- Start with a low dose and gradually titrate upwards to minimize adverse effects 2
- Adverse effects typically appear at doses >60 mg/day 3
- The optimal daily dose of baclofen for MS spasticity ranges between 10 and 80 mg 4
- For patients who cannot tolerate or respond inadequately to oral baclofen, intrathecal baclofen may be considered 3
Alternative Options
- Tizanidine can be considered as an alternative to baclofen for MS patients 4
- In comparative studies, tizanidine showed similar improvement in overall spastic state, spasms, and clonus as baclofen, with potentially better outcomes for muscle strength, bladder function, and activities of daily living 4
- Gabapentin or other alpha-2-delta ligands may be considered for patients with both spasticity and neuropathic pain 5
Monitoring and Side Effects
- Common side effects of baclofen include sedation, excessive weakness, dizziness, mental confusion, and somnolence 3
- The incidence of adverse effects ranges from 10% to 75% but can be minimized by slow titration 3
- Monitor for increased weakness due to loss of spasticity that may be needed for support or activities of daily living 6
- Regular assessment of hepatic, renal, and hematological function is recommended, although studies have shown no significant changes in these parameters with baclofen use 2, 6
Special Considerations
- Baclofen may need to be withdrawn in some patients due to increased weakness or intolerable side effects 7
- Approximately 25-30% of MS patients may fail to respond to oral baclofen 3
- For patients with severe, intractable spasticity unresponsive to oral medications, intrathecal baclofen delivered via pump may be considered 3
- Intrathecal baclofen allows direct drug administration to the cerebrospinal fluid, minimizing central side effects while achieving higher drug levels at the site of action 3
Caution
- Avoid abrupt discontinuation of baclofen as this may precipitate withdrawal symptoms including hallucinations, seizures, and rebound spasticity 3
- Benzodiazepines have limited efficacy in the management of persistent pain and spasticity, with a high risk profile in older adults 8
- The drug is best indicated in patients in whom spasticity is not required for support or other activities of daily living 6