Remeron

[Mirtazapine]

Clinical Pharmacology
PHARMACEUTICAL PARTICULARS

List of excipients

Remeron SolTab 15, 30 and 45 mg tablets contain:

Text Continues Below

---

Sugar spheres, hydroxypropyl methylcellulose, polyvinylpyrrolidone (povidone), magnesium stearate, aminoalkyl methacrylate copolymer E (Eudragit E100), aspartame, citric acid, crospovidone, mannitol, microcrystalline cellulose, natural and artificial orange flavour and sodium bicarbonate.

Pharmacokinetic properties

After oral administration of Remeron, the active constituent mirtazapine is rapidly and well absorbed (bioavailability 50%), reaching peak plasma levels after about 2 hours. Binding of mirtazapine to plasma proteins is approx. 85%. The mean half-life of elimination is 20-40 hours; longer half-lives, up to 65 hours, have occasionally been recorded and shorter half-lives have been seen in young men. The half-life of elimination is sufficient to justify once-a-day dosing. Steady state is reached after 3-4 days, after which there is no further accumulation. Mirtazapine displays linear pharmacokinetics within the recommended dose range. Food intake has no influence on the pharmacokinetics of mirtazapine.

Mirtazapine is extensively metabolized and eliminated via the urine and faeces within a few days. Major pathways of biotransformation are demethylation and oxidation, followed by conjugation. In vitro data from human liver microsomes indicate that cytochrome P450 enzymes CYP2D6 and CYP1A2 are involved in the formation of the 8-hydroxy metabolite of mirtazapine, whereas CYP3A4 is considered to be responsible for the formation of the N-demethyl and N-oxide metabolites.

The demethyl metabolite is pharmacologically active and appears to have the same pharmacokinetic profile as the parent compound.
The clearance of mirtazapine may be decreased as a result of renal or hepatic insufficiency.

Page:  1 | 2 | Next >>