Mirtazapin Aurobindo (Mirtazapine)

Mirtazapine is indicated for major depressive disorder, a mood‑related condition treated by modulating noradrenergic and serotonergic pathways.

• Major depressive disorder: reduces depressive symptoms and improves overall mood in adult patients.
• Depressive episodes in bipolar disorder (adjunct): assists in managing depressive phases when used alongside mood stabilizers.
• Depression with prominent insomnia: promotes sleep while treating depressive symptoms.

• Mirtazapine acts as an antagonist at central presynaptic α2‑adrenergic receptors, disinhibiting norepinephrine release, and blocks postsynaptic 5‑HT2 and 5‑HT3 receptors, enhancing serotonergic transmission through 5‑HT1 receptors. Additionally, it antagonizes histamine H1 receptors, which contributes to its sedative properties and appetite stimulation. The net effect is an increase in central monoamine availability, supporting mood elevation.

Mirtazapine may cause a range of adverse reactions, which are categorized by frequency and severity.

Common Side Effects

• Sedation or drowsiness.
• Increased appetite and weight gain.
• Dry mouth.
• Constipation.
• Dizziness.

Serious or Rare Side Effects

• Agranulocytosis or severe neutropenia.
• Seizures.
• Suicidal thoughts or behavior, especially early in treatment.
• Severe hypersensitivity reactions (e.g., Stevens‑Johnson syndrome).
• Hepatic dysfunction or jaundice.

Before initiating therapy, clinicians should evaluate individual risk factors and monitor patients for specific safety concerns.

• Hepatic function: assess liver enzymes in patients with existing liver disease.
• Suicidal ideation: monitor closely during the first few weeks, especially in younger adults.
• Elderly patients: use caution due to increased risk of sedation and falls.
• Discontinuation: avoid abrupt cessation to reduce the risk of withdrawal symptoms.
• Cardiovascular disease: monitor blood pressure and heart rate as orthostatic changes may occur.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Mirtazapine can interact with several drug classes, requiring careful assessment of concomitant therapies.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of serotonin syndrome.
• Other serotonergic agents (e.g., SSRIs, SNRIs, tramadol): increased serotonin toxicity.
• Central nervous system depressants (e.g., benzodiazepines, alcohol): enhanced sedation and respiratory depression.
• Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine): may raise mirtazapine plasma levels.
• Alcohol: additive sedative effects.

Moderate Interactions (Monitor Closely)

• Antihypertensives: potential additive hypotensive effect.
• Anticholinergic drugs: increased anticholinergic burden.
• Carbamazepine: may reduce mirtazapine concentrations.
• Warfarin: monitor INR for possible alteration.
• Fluconazole: may modestly increase mirtazapine levels.