Mirtazapine

Generic Details

Generic Name

Mirtazapine

Other Names

  • Remeron
  • Avanza
  • Zispin

Drug Class

  • Noradrenergic and specific serotonergic antidepressant (NaSSA)

Chemical Formula

C17H19N3

Molecular Weight

265.352 g/mol

Mechanism of Action

  • Antagonist at central presynaptic alpha2-adrenergic autoreceptors

Indications

  • Major Depressive Disorder
  • Generalized Anxiety Disorder
  • Insomnia
  • Post-traumatic Stress Disorder

Common Dosage Forms

  • Tablet
  • Orally disintegrating tablet

Typical Dosage

  • 15-45 mg daily, usually at bedtime

Pediatric Dosage

  • Not established

Geriatric Dosage

  • Lower starting dose may be necessary for elderly patients

Side Effects

  • Sedation
  • Increased appetite
  • Weight gain
  • Dry mouth
  • Constipation
  • Dizziness

Contraindications

  • Hypersensitivity to mirtazapine
  • Use with MAO inhibitors

Pregnancy Category

  • C

Lactation Safety

  • Considered compatible with breastfeeding by the American Academy of Pediatrics

Drug Interactions

  • MAO inhibitors
  • SSRIs
  • Tramadol
  • Warfarin

Overdose Symptoms

  • Sedation
  • Tachycardia
  • Vomiting
  • Seizures

Antidote for Overdose

  • There is no specific antidote; treatment is supportive

Storage Conditions

  • Store at room temperature away from light and moisture

Pharmacokinetics

  • Absorption: Well-absorbed orally; food does not affect absorption significantly
  • Distribution: Highly protein-bound
  • Metabolism: Metabolized in the liver via CYP2D6 and CYP1A2
  • Excretion: Primarily excreted in urine (75%) and feces (15%)

Precautions

  • Caution in patients with history of seizures
  • Monitor for worsening of depression or suicidal thoughts

Warnings

  • May increase the risk of suicidal thinking and behavior in children, adolescents, and young adults

Others

  • May cause drowsiness; avoid alcohol and operating heavy machinery