Correlation between steady-state plasma concentrations of mianserin and trazodone in depressed patients.
OBJECTIVE
The correlations between steady-state plasma concentrations of mianserin and its active metabolite desmethylmianserin and those of trazodone and its active metabolite m-chlorophenylpiperazine (m-CPP) were examined in 19 depressed patients.


METHODS
Ten patients received first mianserin (30 mg per day) and second trazodone (150 mg per day), while 9 patients received these treatments in the opposite sequence, with at least 2-week intervals between the two phases. Blood was sampled at steady state, 1-3 weeks after initiation of each treatment. Plasma concentrations of mianserin, the separate enantiomers S(+)- and R(-)-mianserin, desmethylmianserin, trazodone and m-CPP were measured by means of high-performance liquid chromatography.


RESULTS
There was a significant correlation between steady-state plasma concentrations of trazodone and total mianserin (r = 0.59) or S(+)-mianserin (r = 0.57), but not R(-)-mianserin (r = 0.33).


CONCLUSIONS
The present study thus suggests that the metabolic capacity of mianserin, especially the more active S(+)-enantiomer, and that of trazodone correlate to each other. This finding supports the previous suggestions that cytochrome P4502D6 is involved in the metabolism of mianserin and trazodone.
Otani
K
K
Department of Neuropsychiatry, Hirosaki University Hospital, Japan.
Tybring
G
G
Mihara
K
K
Yasui
N
N
Kaneko
S
S
Ohkubo
T
T
Nagasaki
T
T
Sugawara
K
K
D018687:Antidepressive Agents, Second-Generation / Q000097:blood / Q000493:pharmacokinetics*; D019389:Cytochrome P-450 CYP2D6 / Q000378:metabolism*; D003863:Depression / Q000188:drug therapy / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008803:Mianserin / Q000097:blood / Q000493:pharmacokinetics*; D008875:Middle Aged; D014196:Trazodone / Q000097:blood / Q000493:pharmacokinetics*
D018687:Antidepressive Agents, Second-Generation; D008803:Mianserin; D019389:Cytochrome P-450 CYP2D6; D014196:Trazodone