Products
Mirtazapine is commercially available in the form of film-coated tablets and meltable tablets (Remeron, generics). It has been approved in many countries since 1999.
Structure and properties
Mirtazapine (C17H19N3, Mr = 265.35 g/mol) is a racemate and exists as a white crystalline powder that is sparingly soluble in water. It is structurally closely related to the tetracyclic antidepressant mianserin. It is a pyrazine and pyridobenzazepine derivative.
Effects
Mirtazapine (ATC N06AX11) has antidepressant, antihistamine, and depressant properties. The effects are due to enhanced central noradrenergic and serotonergic activity. Mirtazapine is an antagonist at central presynaptic alpha2-adrenoceptors and an antagonist at 5-HT2 and 5-HT3 and histamine H1 receptors. It has a long half-life between 20 to 40 hours.
Indications
For acute treatment and maintenance therapy of unipolar depressive episode. Mirtazapine is also prescribed off-label for sleep disorders but is not officially approved for this purpose.
Dosage
According to the prescribing information. The medication is taken once daily in the evening before bedtime. The intake is independent of meals.
Contraindications
- Hypersensitivity
- Combination with MAO inhibitors
For complete precautions, see the drug label.
Interactions
Mirtazapine is metabolized by CYP2D6, CYP1A2, and CYP3A4. Corresponding drug-drug interactions are possible. Other interactions may occur with MAO inhibitors, serotonergic agents, sedatives, alcohol, and warfarin.
Adverse effects
The most common possible adverse effects include drowsiness, dullness, dry mouth, increased appetite, weight gain, dizziness, and fatigue.