SPASTICITY-CLONIDINE & TIZANIDINE

SUMMARY

1. Centrally acting alpha₂-adrenergic agonists that act negatively on the pontine locus cereleus (produces norepinephrine in response to stressful stimuli) resulting in pre-synaptic inhibitory modulation of spinal reflexes.

2. Used in SCI, TBI and MS.

3. Clonidine dosage: 0.1-0.3mg transdermal patch/week; tizanidine dosage: 2-4mg/day.

4. Adverse effects: hypotension (presents as exaggerated postural drop in SCI), sedation, bradycardia, dry mouth, dizziness, hepatotoxicity, impotence.

5. Withdrawal after long-term use may lead to severe hypertensive crisis, may impair hypoglycemia-induced tachycardia.

6. Interacts with Ciprofloxacin & Fluvoxamine (CYP1A2 inhibitors).

Reference(s)

Cifu, D.X. (2020). Braddom’s physical medicine and rehabilitation. Elsevier. Get it on Amazon.
Cuccurullo, S. (2019). Physical medicine and rehabilitation board review. New York: Demosmedical. Get it on Amazon.
O’Young, B., Young, M.A. and Stiens, S.A. (2008). Physical Medicine and Rehabilitation Secrets. Mosby. Get it on Amazon.