Miron Smelt (Mirtazapine)

Mirtazapine is used within the antidepressant drug class to treat mood disorders.

• Major depressive disorder: alleviates depressive symptoms and improves mood.
• Depression with prominent anxiety: reduces both depressive and anxiety features.
• Treatment‑resistant depression (off‑label): may be added when first‑line agents are insufficient.

• Mirtazapine antagonizes central presynaptic α2‑adrenergic receptors, increasing norepinephrine release, and blocks postsynaptic 5‑HT2 and 5‑HT3 receptors, enhancing serotonergic neurotransmission. Its potent H1‑histamine antagonism also contributes to its pharmacologic profile, collectively producing antidepressant effects.

Mirtazapine may cause a range of adverse reactions.

Common Side Effects

• Drowsiness: feeling unusually sleepy or fatigued.
• Increased appetite: heightened hunger leading to weight gain.
• Dry mouth: reduced salivation causing oral discomfort.
• Constipation: slowed gastrointestinal transit.
• Dizziness: light‑headed sensation, especially on standing.
• Edema: mild swelling of the lower extremities.

Serious or Rare Side Effects

• Agranulocytosis: severe reduction in white blood cells.
• Severe hepatic impairment: abnormal liver function tests.
• Suicidal thoughts: emergence or worsening of suicidal ideation.
• Seizures: rare occurrence of convulsive episodes.
• Hypersensitivity reactions: rash, angioedema, or anaphylaxis.

Before initiating therapy, clinicians should consider several safety aspects.

• Pregnancy: safety not established; weigh benefits against potential risks.
• Breastfeeding: unknown excretion; consider alternative treatment.
• Elderly patients: monitor for increased sedation and falls.
• Concomitant CNS depressants: may enhance drowsiness.
• Liver impairment: dose adjustment may be required.
• Store at ambient temperature: keep in original container, protect from moisture and direct sunlight.

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

Major Interactions (Avoid)

• MAO inhibitors: risk of hypertensive crisis or serotonin syndrome.
• CNS depressants (e.g., benzodiazepines, opioids): additive sedation and respiratory depression.

Moderate Interactions (Monitor Closely)

• CYP2D6 inhibitors (e.g., fluoxetine, paroxetine): may increase mirtazapine plasma levels.
• Anticholinergic agents: heightened anticholinergic burden.
• Alcohol: enhances central nervous system depression.
• Other serotonergic drugs: potential for serotonin syndrome, though risk is lower than with SSRIs.