Mirtazapin Stada (Mirtazapine)

Mirtazapine is a NaSSA antidepressant used primarily in the treatment of mood disorders.

• Major depressive disorder: reduces depressive symptoms and improves overall mood.
• Depressive episodes with insomnia: promotes better sleep quality.
• Depressive episodes with loss of appetite: stimulates appetite and weight gain.

• Mirtazapine antagonizes central presynaptic α2‑adrenergic receptors, leading to increased release of norepinephrine and serotonin. It also blocks 5‑HT2, 5‑HT3 and H1 receptors, which contributes to its antidepressant, anxiolytic, and sedative properties without directly stimulating serotonin reuptake.

Mirtazapine may cause a range of adverse reactions, from mild to serious.

Common Side Effects

• Sedation or drowsiness
• Increased appetite and weight gain
• Dry mouth
• Constipation
• Dizziness
• Enhanced appetite leading to weight gain

Serious or Rare Side Effects

• Agranulocytosis or severe neutropenia
• Severe allergic reactions (e.g., angioedema, anaphylaxis)
• Stevens‑Johnson syndrome or toxic epidermal necrolysis
• Suicidal thoughts or worsening depression
• Hepatic dysfunction or jaundice
• Seizures (rare).

Before initiating therapy, clinicians should consider several safety aspects.

• Hepatic function: assess liver enzymes in patients with hepatic impairment.
• Mood monitoring: watch for worsening depression or emergence of suicidal ideation.
• Cardiovascular status: use caution in patients with known heart disease.
• Elderly patients: start at lower doses due to increased sensitivity to sedation.
• Discontinuation: avoid abrupt cessation to reduce risk of rebound insomnia.
• Store at below 25°C: keep in the original packaging, protect from moisture and light.

Mirtazapine can interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis.
• CNS depressants (e.g., benzodiazepines, opioids): additive sedation.
• Strong CYP2D6 inhibitors (e.g., fluoxetine, paroxetine): increase mirtazapine plasma levels.
• Alcohol: may enhance sedative effects.
• Other serotonergic agents: potential for serotonin syndrome.

Moderate Interactions (Monitor Closely)

• CYP3A4 inducers (e.g., carbamazepine, phenytoin): may reduce efficacy.
• Antihistamines: may increase anticholinergic burden.
• Warfarin: monitor INR for possible anticoagulant effect alteration.
• Lithium: observe lithium levels for potential toxicity.