Tizanidine Hydrochloride

Generic Details

Generic Name

Tizanidine Hydrochloride

Other Names

  • Zanaflex

Drug Class

  • Antispasmodic

Chemical Formula

C9H8ClN5S

Molecular Weight

253.7 g/mol

Mechanism of Action

  • Acts as a centrally acting alpha-2 adrenergic agonist

Indications

  • Muscle spasticity
  • Muscle tone disorders

Common Dosage Forms

  • Tablet
  • Capsule

Typical Dosage

  • 2-4 mg every 6-8 hours orally

Pediatric Dosage

  • Not recommended for use in children under 18 years

Geriatric Dosage

  • Lower initial doses may be required in elderly patients

Side Effects

  • Drowsiness
  • Dizziness
  • Dry mouth
  • Weakness
  • Hypotension

Contraindications

  • Hypersensitivity to tizanidine
  • Use with fluvoxamine or ciprofloxacin

Pregnancy Category

  • C - Risk cannot be ruled out

Lactation Safety

  • Not recommended during breastfeeding, potential risk to the infant

Drug Interactions

  • May interact with CNS depressants
  • May enhance hypotensive effects of antihypertensive agents

Overdose Symptoms

  • Severe drowsiness
  • Hypotension
  • Respiratory depression
  • Coma

Antidote for Overdose

  • Naloxone

Storage Conditions

  • Store at room temperature away from moisture and heat

Pharmacokinetics

  • Absorption: Rapidly absorbed from the gastrointestinal tract
  • Distribution: Crosses the blood-brain barrier and placenta; distributed into breast milk
  • Metabolism: Metabolized in the liver
  • Excretion: Excreted in the urine as unchanged drug and metabolites

Precautions

  • Caution in patients with renal or hepatic impairment
  • Avoid abrupt discontinuation

Warnings

  • May cause hypotension and sedation; caution while driving or operating machinery

Others

  • Tizanidine should be used with caution in patients with a history of hypotension, liver disease, or renal impairment.