Tizanidine vs Baclofen for Muscle Spasticity

Mechanisms and Indications

Baclofen is a GABAB agonist primarily used for spasticity management, according to the American Academy of Neurology 1

For severe spasticity unresponsive to oral medications, intrathecal baclofen may be considered, as recommended by the American Academy of Physical Medicine and Rehabilitation 1
Botulinum toxin (onaBoNT-A) was found to be superior to tizanidine for patients with upper limb spasticity, as reported by the American Family Physician 2, 3

For focal spasticity, consider botulinum toxin as first-line pharmacological treatment, as suggested by the American Academy of Neurology 1
For generalized spasticity, if long-term continuous effect is needed, baclofen may be more suitable due to its longer duration of action, according to the American Academy of Physical Medicine and Rehabilitation 4
For severe, refractory spasticity, consider intrathecal baclofen, as recommended by the American Academy of Neurology 1, 4

The American Geriatrics Society recommends an initial dosing of baclofen at 5 mg up to three times daily to minimize side effects and optimize tolerability, especially in older adults 5, 6
Titration should be gradual, as older persons rarely tolerate doses greater than 30 to 40 mg per day, according to the American Geriatrics Society 5, 6
Tizanidine may be considered as an alternative with a starting dose of 2 mg up to three times daily, as suggested by the American Geriatrics Society 5, 6

Patients on baclofen therapy should be closely monitored for muscle weakness, urinary function changes, cognitive effects, and sedation, as recommended by the American Geriatrics Society 5, 6
Abrupt discontinuation of baclofen should be avoided as it can cause central nervous system irritability and potentially severe withdrawal symptoms, according to the American Geriatrics Society 5, 6

Tizanidine is a centrally acting alpha-2 adrenergic agonist that reduces spasticity through central mechanisms 7
Diazepam and other benzodiazepines act centrally through GABA enhancement and are not recommended during stroke recovery due to potential negative effects on recovery 8
Tizanidine: Centrally acting alpha-2 adrenergic agonist that reduces muscle tone 9
Diazepam: GABA₍A₎ agonist that acts centrally and is associated with sedation and potential negative effects on recovery 10

For patients with velocity-dependent increase in muscle tone and hyperreflexia following spinal cord injury, consider initial non-pharmacological approaches: positioning, range of motion exercises, stretching 8
For persistent spasticity causing pain or functional limitations, dantrolene is appropriate when direct action on skeletal muscle is desired 9
Alternative options include tizanidine or baclofen when central mechanisms are preferred 7
For focal spasticity, consider botulinum toxin injections 8
For severe, refractory spasticity, consider intrathecal baclofen 11

Dantrolene carries a black box warning for potentially fatal hepatotoxicity, occurring in approximately 0.1-0.2% of patients on long-term treatment 12