[Gender- and age-related differences in  dosage and serum concentration of psychotropic drugs].
BACKGROUND
The dose recommendations in the Norwegian Pharmaceutical Product Compendium (Felleskatalogen) are not gender-specific, despite evidence of gender-dependent differences in the metabolism of a number of drugs. The purpose of this study was to investigate the extent to which age and gender influence the prescription and serum concentration of psychotropic drugs.


METHODS
The prescribed doses and serum concentrations of antidepressant, antipsychotic and antiepileptic drugs were studied in relation to age and gender in 1533 patients.


RESULTS
Elderly women (≥ 65 years) were given somewhat lower doses of antidepressant drugs, but they had significantly higher serum concentrations than younger patients of either gender. Antidepressant drugs were prescribed in fairly high doses in the study population; the median number of defined daily doses was 1.5.


CONCLUSIONS
The study suggests that when prescribing drugs, Norwegian physicians do not take sufficient account of the effect of age and gender on the pharmacokinetics of antidepressant drugs.
Seksjon for psykiatrisk forskning og undervisning, Diakonhjemmet Sykehus, Norway. kjellpb@extern.uio.no
Kjell Petter
KP
Bøgwald
Ida
I
Rudberg
Lars
L
Tanum
Helge
H
Refsum
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000927:Anticonvulsants / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D000928:Antidepressive Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D014150:Antipsychotic Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D002380:Catalogs, Drug as Topic; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D012016:Reference Values; D012737:Sex Factors
D000927:Anticonvulsants; D000928:Antidepressive Agents; D014150:Antipsychotic Agents