Spalex®

Muscle spasm and/or musculoskeletal pain:

2 to 4 mg every 6 to 12 hours as needed and/or at bedtime

Spasticity:

2 mg once daily usually at bedtime; may increase based on response and tolerability by 2 to 4 mg per day

Contraindications:

Concomitant therapy with ciprofloxacin or fluvoxamine (potent CYP1A2 inhibitors)

Interactions:

Amiodarone: May increase the serum concentration of TiZANidine. Risk C: Monitor therapy

Angiotensin-Converting Enzyme Inhibitors: TiZANidine may enhance the hypotensive effect of AngiotensinConverting Enzyme Inhibitors. Risk C: Monitor therapy

Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may enhance the hypotensive effect of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor therapy

Beta-Blockers: Alpha2-Agonists may enhance the AV-blocking effect of Beta-Blockers. Sinus node dysfunction may also be enhanced. Beta-Blockers may enhance the rebound hypertensive effect of Alpha2-Agonists. This effect can occur when the Alpha2-Agonist is abruptly withdrawn. Management: Closely monitor heart rate during treatment with a beta blocker and clonidine. Withdraw beta blockers several days before clonidine withdrawal when possible, and monitor blood pressure closely. Recommendations for other alpha2-agonists are unavailable. Risk D: Consider therapy modification

CYP1A2 Inducers (Moderate): May decrease the serum concentration of TiZANidine. Risk C: Monitor therapy

 CYP1A2 Inhibitors (Moderate): May increase the serum concentration of TiZANidine. Management: If combined use cannot be avoided, initiate tizanidine in adults at 2 mg and increase in 2 to 4 mg increments based on patient response. Monitor for increased effects of tizanidine, including adverse reactions. Risk D: Consider therapy modification

CYP1A2 Inhibitors (Strong): May increase the serum concentration of TiZANidine. Risk X: Avoid combination

CYP1A2 Inhibitors (Weak): May increase the serum concentration of TiZANidine. Management: Avoid these combinations when possible. If combined use is necessary, initiate tizanidine at an adult dose of 2 mg and increase in 2 to 4 mg increments based on patient response. Monitor for increased effects of tizanidine, including adverse reactions. Risk D: Consider therapy modification

Fingolimod: Bradycardia-Causing Agents may enhance the bradycardic effect of Fingolimod. Management: Consult with the prescriber of any bradycardia-causing agent to see if the agent could be switched to an agent that does not cause bradycardia prior to initiating fingolimod. If combined, perform continuous ECG monitoring after the first fingolimod dose. Risk D: Consider therapy modification

Pregnancy and Lactation:

Information related to use of tizanidine in pregnancy is limited

The decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and the benefits of treatment to the mother.

Warning and Precaution:

• Hepatic effects: Potential for hepatotoxicity; monitor aminotransferases prior to and during use or if hepatic injury is suspected.
• Hypersensitivity reactions: Hypersensitivity reactions, including anaphylaxis, angioedema, respiratory compromise, and urticaria have been reported with use. Patients with signs and symptoms of allergic reactions should discontinue therapy.
• Hypotension: Significant hypotension and syncope may occur; use with caution in patients at risk for severe hypotensive effects (eg, patients taking concurrent medications which may predispose to hypotension). Minimize effects by titrating dose and monitoring for signs and symptoms of hypotension prior to dose increase.
• Sedation: Sedation may occur; use with caution in patients at risk for sedative effects (eg, patients taking concurrent CNS depressants); patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).
• Visual hallucinations: Use has been associated with visual hallucinations or delusions; use caution in patients with psychiatric disorders. Consider discontinuation of therapy if hallucinations occur.

 Adverse Reactions:

Gastrointestinal: Xerostomia (49%)

Nervous system: Dizziness (16%), drowsiness (48%)

Storage:

Store below 30ºC and protect from light and moisture.