Drug Name
Generic Name : tizanidine
Brand Name: Zanaflex
Classification: Antispasmodic, Sympatholytic, centrally acting
Pregnancy Category C
Dosage & Route
Available forms: Tablets—2, 4 mg; capsules—2, 4, 6 mg
ADULTS
- 8 mg PO initial dose; repeat as needed q 6–8 hr; maximum dose, 36 mg/day.
PEDIATRIC PATIENTS
- Safety and efficacy not established.
PATIENTS WITH RENAL IMPAIRMENT
- Use lower doses, monitor response.
Therapeutic actions
- Tizanidine, an α2-adrenergic agonist, is a centrally acting muscle relaxant structurally related to clonidine. It reduces spasticity by increasing presynaptic inhibition of motor neurons and has no direct effect on skeletal muscle, the neuromuscular junction or on monosynaptic spinal reflexes.
Indications
- Acute and intermittent management of increased muscle tone associated with spasticity
Adverse effects
- Drowsiness, fatigue, dizziness, insomnia, headache, anxiety, nausea, dryness of mouth, GI disturbances, hypotension, bradycardia, muscle pain and weakness, transient increase in serum transaminases, hallucinations.
- Potentially Fatal: Hepatitis.
Contraindications
- Severe hepatic dysfunction.
Nursing considerations
Assessment
- History: Hypersensitivity to tizanidine, clonidine; hepatic or renal impairment, hypotension; pregnancy, lactation
- Physical: Mucous membranes—color, lesions; orientation, affect; P, BP, orthostatic BP; perfusion; liver evaluation; LFTs, renal function tests
Interventions
- Administer drug q 6–8 hr around-the-clock for best effects.
- Adjust drug dosage slowly, which helps to decrease side effects.
- Continue all supportive measures used for spinal cord–injured or neurologically damaged patients.
- Provide sugarless lozenges or ice chips, as appropriate, if dry mouth or altered taste occurs.
- Establish safety precautions if CNS or hypotensive changes occur (use side rails, accompany patient when ambulating).
- Attempt to lower dose if side effects become severe or intolerable.
Teaching points
- Take this drug exactly as prescribed. It is important that you not miss doses. Consult your health care provider to determine a schedule that will not interfere with rest.
- Continue all other supportive measures for your condition.
- You may experience these side effects: Drowsiness, dizziness, lightheadedness, headache, weakness (use caution while driving or performing tasks that require alertness or physical dexterity); dry mouth (suck on sugarless lozenges or ice chips); GI upset (eat frequent small meals); dizziness, lightheadedness when changing position (rise slowly, use caution when transferring).
- Report changes in urine or stool, severe dizziness or passing out, changes in vision, difficulty swallowing.