The pharmacokinetics of mianserin in elderly depressed patients

The pharmacokinetics of mianserin were examined in eight elderly depressed patients following a single oral dose of 60 mg. Plasma concentrations were measured by gas chromatography/mass spectrometry and the data analyzed using a two-compartment open model. Mean (+/- SD) estimates were: absorption half-life 0.8 +/- 1.0h, peak concentration 117 +/- 23 micrograms/l, peak time 2.2 +/- 1.3h, distribution half-life 3.4 +/- 1.2h, elimination half-life 33 +/- 15h, apparent volume of distribution 20.2 +/- 7.9 1/kg, and oral clearance 0.49 +/- 0.21 l/kg/h. These parameters were not significantly different from those found in healthy volunteers. The absorption lag time (0.6 +/- 0.2h) and area under the curve (2009 +/- 566 micrograms/l/h) were significantly different in the elderly. The clinical implications of these differences for the treatment of elderly depressed patients are discussed.