Mirtazapine
Classification: BATC code: N06AX11
Summary
Published controlled studies on differences between men and women regarding the effect of mirtazapine are lacking.
Mirtazapine is metabolized more slowly in women who thus achieve higher serum concentrations than men.
One study showed that men were more likely than women to discontinue antidepressive medication.
In our opinion, the described differences do not motivate differentiated dosing or treatment in men and women.
Additional information
Pharmacokinetics and dosing
Several studies have shown the pharmacokinetics properties of mirtazapine to be different in men and women [1,2,3]. The mean elimination half-life of mirtazapine is longer in women than in men (37 h vs. 26 h) [4]. In a study of 30 mg mirtazapine daily to 32 women and 13 men for 14 days, women had higher plasma concentrations of the enantiomers of mirtazapine and its demethyl metabolite [2]. In another pharmacokinetic study (36 men, 36 women), the concentration of mirtazapine was analyzed after intake of a single 30 mg dose of mirtazapine. Dose-weight adjusted AUC was about 15% lower in women and the dose/weight adjusted Cmax was slightly higher in women [3].
Pharmacokinetic variations of mirtazapine and its demethyl metabolite were examined in a therapeutic drug monitoring (TDM) study (110 men, 253 women). Median dose-corrected concentrations of mirtazapine, demethylmirtazapine and demethylmirtazapine/mirtazapine ratio were significantly higher in women than in men [5]. In another TDM study (303 men, 357 women), women had higher mirtazapine (30 mg/day) concentrations than men (107 vs. 92 nmol/L) [6].
Effects
No studies with a clinically relevant sex analysis regarding effects of mirtazapine have been found.
Adverse effects
No studies with a clinically relevant sex analysis regarding adverse effects of mirtazapine have been found.
Reproductive health issues
Regarding teratogenic aspects, please consult the Drugs and Birth Defects Database (in Swedish, Janusmed fosterpåverkan).
Other information
In a Spanish study based on a prescription database, 7525 patients who had received one or more antidepressant drug were included. Male sex was associated with a greater risk of treatment drop-out compared to women [7]. The prescription history during the first year after the introduction of mirtazapine, sertraline and venlafaxine were collected from 20 pharmacies in the Netherlands. No differences between men or women were observed [8]. In an Australian national survey, the prevalence and treatment of affective and anxiety disorder were estimated. Both prevalence and treatment were higher in women (5.25 vs. 4.53 DDD/1000 population/day) [9].
Updated: 2019-02-26
Date of litterature search: 2013-04-05
References
- Timmer CJ, Sitsen JM, Delbressine LP. Clinical pharmacokinetics of mirtazapine. Clin Pharmacokinet 2000 Jun;38(6):461-74 PubMed
- Jaquenoud Sirot E, Harenberg S, Vandel P, Lima CA, Perrenoud P, Kemmerling K et al. Multicenter study on the clinical effectiveness, pharmacokinetics, and pharmacogenetics of mirtazapine in depression. J Clin Psychopharmacol. 2012;32:622-9. PubMed
- Borobia AM, Novalbos J, Guerra-López P, López-Rodríguez R, Tabares B, Rodríguez V et al. Influence of sex and CYP2D6 genotype on mirtazapine disposition, evaluated in Spanish healthy volunteers. Pharmacol Res. 2009;59:393-8. PubMed
- Mirtazapine Remedyrepack inc (mirtazapine). DailyMed [www]. US National Library of Medicine. [updated 2012-10-01, cited 2013-04-18]. länk
- Reis M, Prochazka J, Sitsen A, Ahlner J, Bengtsson F. Inter- and intraindividual pharmacokinetic variations of mirtazapine and its N-demethyl metabolite in patients treated for major depressive disorder: a 6-month therapeutic drug monitoring study. Ther Drug Monit. 2005;27:469-77. PubMed
- Reis M, Aamo T, Spigset O, Ahlner J. Serum concentrations of antidepressant drugs in a naturalistic setting: compilation based on a large therapeutic drug monitoring database. Ther Drug Monit. 2009;31:42-56. PubMed
- Serna MC, Cruz I, Real J, Gascó E, Galván L. Duration and adherence of antidepressant treatment (2003 to 2007) based on prescription database. Eur Psychiatry. 2010;25:206-13. PubMed
- Egberts AC, Lenderink AW, de Koning FH, Leufkens HG. Channeling of three newly introduced antidepressants to patients not responding satisfactorily to previous treatment. J Clin Psychopharmacol. 1997;17:149-55. PubMed
- Hollingworth SA, Burgess PM, Whiteford HA. Affective and anxiety disorders: prevalence, treatment and antidepressant medication use. Aust N Z J Psychiatry. 2010;44:513-9. PubMed
- Läkemedelsstatistik. Stockholm: Socialstyrelsen. 2015 [cited 2016-04-29] länk
Reviewed by: Expertrådet för psykiatriska sjukdomar, Expertrådet för geriatriska sjukdomar
Approved by: Mia von Euler