What is the recommended dose increase for tizanidine (Zanaflex) for muscle spasm?

Tizanidine Dosage Increase for Muscle Spasm

For tizanidine (Zanaflex), you can safely increase the dose from 2 mg three times daily to 4 mg three times daily, with further gradual increases of 2-4 mg per step as needed, not exceeding a maximum daily dose of 36 mg.

Dosing Guidelines

The FDA-approved dosing for tizanidine follows a gradual titration approach:

• Starting dose: 4 mg (though you're currently on 2 mg TID)
• Titration: Increase by 2-4 mg increments
• Dosing frequency: Every 6-8 hours as needed
• Maximum daily dose: 36 mg (not to exceed 3 doses in 24 hours) 1
• Maximum single dose: Generally not exceeding 12 mg per dose 1

Recommended Titration Schedule

1. Current dose: 2 mg three times daily (6 mg total)
2. First increase: 4 mg three times daily (12 mg total)
3. Further increases: If needed, increase by 2-4 mg per dose every 1-2 weeks
4. Evaluate effect: Peak effect occurs at 1-2 hours after dosing and lasts 3-6 hours 1

Important Considerations

Side Effects to Monitor

• Dose-dependent sedation and drowsiness (most common)
• Dizziness
• Dry mouth
• Hypotension
• Bradycardia 2

Contraindications

• Concomitant use with CYP1A2 inhibitors (e.g., ciprofloxacin, fluvoxamine)
• Significant hepatic or renal dysfunction
• Elderly patients may require lower doses 2, 3

Drug Interactions

• Avoid combining with:
  • Other CNS depressants (increased sedation risk)
  • CYP1A2 inhibitors including oral contraceptives, acyclovir, amiodarone, verapamil, cimetidine, and famotidine 2, 3

Special Considerations

Timing with Food

Food has complex effects on tizanidine pharmacokinetics that may affect onset and intensity of action. Try to be consistent with taking the medication either with or without food 1.

Discontinuation

If you need to stop tizanidine after long-term use, it should be tapered gradually to prevent withdrawal symptoms including rebound hypertension, tachycardia, and hypertonia 2, 3.

Alternative Options

If tizanidine is not effective or poorly tolerated, alternative muscle relaxants like baclofen or cyclobenzaprine might be considered, though these have different side effect profiles 4.

Remember that the effects of tizanidine are dose-related, and finding the optimal dose requires balancing efficacy against side effects. Most patients find effective relief at doses between 8-24 mg per day 5.