MIRTAZAPINE-WGR

What it is

MIRTAZAPINE-WGR is available as orally disintegrating tablets in strengths of 15 mg, 30 mg and 45 mg mirtazapine. The tablet disintegrates on the tongue and can be swallowed with or without water.

Approved indications

— Treatment of major depression including relapse prevention

Dosing overview

Treatment should begin with 15 mg daily. The effective daily dose is usually between 30 and 45 mg, but responses have been observed at 60 mg per day. Mirtazapine has a half-life of 20-40 hours and should be taken preferably as a single night-time dose before going to bed. The recommended dose for elderly patients is the same as that for adults, though dosing increases should be undertaken under close supervision. Mirtazapine begins to exert its effect after 1-2 weeks of treatment, with treatment at an adequate dose resulting in a positive response within 2-4 weeks.

Key safety warnings

The risk of suicidality is inherent in depression and may persist until significant remission occurs. Patients should be closely monitored for clinical worsening and suicidality, especially at the beginning of a course of treatment or at the time of dose changes. Bone marrow depression, usually presenting as granulocytopenia or agranulocytosis, has been reported during treatment with mirtazapine, with symptoms mostly appearing after 2-6 weeks of treatment. One should be alert for symptoms like fever, sore throat, stomatitis or other signs of infections, and if such symptoms occur the treatment should be stopped and blood counts taken. Severe cutaneous adverse reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, bullous dermatitis and erythema multiforme, which can be life-threatening or fatal, have been reported in association with mirtazapine treatment, and mirtazapine should be withdrawn immediately if signs and symptoms of these reactions appear. Hyponatremia has been reported very rarely with the use of mirtazapine, and caution should be exercised in patients at risk, such as elderly patients or patients concomitantly treated with medications known to cause hyponatremia.

Contraindications

Hypersensitivity to mirtazapine or to any of the excipients is a contraindication. MAO Inhibitors are contraindicated as concomitant therapy, and mirtazapine should not be used in combination with MAO Inhibitors, or within 14 days of initiating or discontinuing therapy with a MAO Inhibitor.

Regulatory history

MIRTAZAPINE-WGR was first listed on the ARTG on 16 February 2024 across three product registrations covering 15 mg, 30 mg and 45 mg tablet strengths.