Assessing drug-drug interactions through therapeutic drug monitoring when administering oral second-generation antipsychotics

References

• Cozza KL, Armstrong SC, Oesterheld JR. Concise guide to drug interaction principles for medical practice: cytochrome P450s, UGTs, P-glycoproteins. 2nd ed. Washington, DC: American Psychiatric Association; 2003.
   Google Scholar
• Johannessen Landmark C, Patsalos PN. Methodologies used to identify and characterise interactions among antiepileptic drugs. Exp Rev Clin Pharmacol. 2012;5:281–292.
   PubMed Web of Science ®Google Scholar
• FDA Guidance for Industry Drug Interaction Studies Study Design, Data Analysis, Implications for Dosing, and Labeling Recommendations. 2012. [cited 2015 Nov 10]. http://www.fda.gov/drugs/developmentapprovalprocess/developmentresources/druginteractionslabeling/ucm093664.htm#classInhibit
   Google Scholar
• Gex-Fabry M, Balant-Gorgia AE, Balant LP. Therapeutic drug monitoring databases for postmarketing surveillance of drug-drug interactions. Drug Saf. 2001;24:947–959.
   PubMed Web of Science ®Google Scholar
• Stahl SM. Antipsychotic agents. In: Stahl SM, editor. Stahl’s essential psychopharmacology. 4th ed. New York: Cambridge University Press; 2013. p. 129–236.
   Google Scholar
• Prior TI, Baker GB. Interactions between the cytochrome P450 system and the second-generation antipsychotics. J Psychiatry Neurosci. 2003;28:99–111.
   PubMed Web of Science ®Google Scholar
• Raggi MA, Mandrioli R, Sabbioni C, et al. Atypical antipsychotics: pharmacokinetics, therapeutic drug monitoring and pharmacological interactions. Curr Med Chem. 2004;11:279–296.
   PubMed Web of Science ®Google Scholar
• Spina E, de Leon J. Metabolic drug interactions with newer antipsychotics: a comparative review. Basic Clin Pharmacol Toxicol. 2007;100:4–22.
   PubMed Web of Science ®Google Scholar
• Conley RR, Kelly DL. Drug-drug interactions associated with second-generation antipsychotics: considerations for clinicians and patients. Psychopharmacol Bull. 2007;40:77–97.
   PubMed Web of Science ®Google Scholar
• Urichuk L, Prior TI, Dursun S, et al. Metabolism of atypical antipsychotics: involvement of cytochrome P450 enzymes and relevance for drug-drug interactions. Curr Drug Metab. 2008;9:410–418.
   PubMed Web of Science ®Google Scholar
• Sheehan JJ, Sliwa JK, Amatniek JC, et al. Atypical antipsychotic metabolism and excretion. Curr Drug Metab. 2010;11:516–525.
   PubMed Web of Science ®Google Scholar
• de Leon J, Santoro V, D’Arrigo C, et al. Interactions between antiepileptics and second-generation antipsychotics. Expert Opin Drug Metab Toxicol. 2012;8:2–24.
   Web of Science ®Google Scholar
• Kennedy WK, Jann MW, Kutscher EC. Clinically significant drug interactions with atypical antipsychotics. CNS Drugs. 2013;12:1021–1048.
   Web of Science ®Google Scholar
• Spina E, de Leon J. Clinically relevant interactions between newer antidepressants and second-generation antipsychotics. Exp Opin Drug Metab Toxicol. 2014;10:721–746.
   PubMed Web of Science ®Google Scholar
• Hiemke C, Baumann P, Bergemann N, et al. AGNP consensus guidelines for therapeutic drug monitoring in psychiatry: update 2011. Pharmacopsychiatry. 2011;44:195–235.
   Web of Science ®Google Scholar
• de Leon J, Armstrong SC, Cozza KL. The dosing of atypical antipsychotics. Psychosomatics. 2005;46:262–273.
   PubMed Web of Science ®Google Scholar
• Smith T, Riskin J. Effect of clozapine on plasma nortriptyline concentration. Pharmacopsychiatry. 1994;27:41–42.
   PubMed Web of Science ®Google Scholar
• Rogers T, de Leon J, Atcher D. Possible interaction between warfarin and quetiapine. J Clin Psychopharmacol. 1999;19:382–383.
   PubMed Web of Science ®Google Scholar
• Yang FW, Liang CS. Multiple intracerebral hemorrhages in an elderly patient after adding quetiapine to a stable warfarin regimen. Gen Hosp Psychiatry. 2011;33:302.e1e 2.
   Google Scholar
• Chen TY, Lin CE, Chen LF, et al. Enhanced bleeding risk in an elderly dementia patient treated with warfarin and quetiapine. J Neuropsychiatry Clin Neurosci. 2013;25:E25.
   PubMed Web of Science ®Google Scholar
• Galetin A, Gertz M, Houston JB. Contribution of intestinal cytochrome p450-mediated metabolism to drug-drug inhibition and induction interactions. Drug Metab Pharmacokinet. 2010;25:28–47.
   PubMed Web of Science ®Google Scholar
• Moons T, De Roo M, Clees S, et al. Relationship between P-glycoprotein and second generation antipsychotics. Pharmacogenomics. 2011;12:1193–1211.
   PubMed Web of Science ®Google Scholar
• de Leon J. The effects of antiepileptic inducers in neuropsychopharmacology, a neglected issue. Part II: pharmacological issues and further understanding. Rev Psiquiatr Salud Ment. 2015;8:167–188.
   PubMed Web of Science ®Google Scholar
• Hefner G, Laib AK, Sigurdsson H, et al. The value of drug and metabolite concentration in blood as a biomarker of psychopharmacological therapy. Int Rev Psychiatry. 2013;25:494–508.
   PubMed Web of Science ®Google Scholar
• Baumann P, Hiemke C, Ulrich S, et al. The AGNP-TDM expert group consensus guidelines: therapeutic drug monitoring in psychiatry. Pharmacopsychiatry. 2004;37:243–265.
   PubMed Web of Science ®Google Scholar
• Mandrioli R, Protti M, Mercolini R. Novel atypical antipsychotics: metabolism and therapeutic drug monitoring. Curr Drug Metab. 2015;16:141–151.
   PubMed Web of Science ®Google Scholar
• Mauri MC, Volonteri LS, Colasanti A, et al. Clinical pharmacokinetics of atypical antipsychotics. A critical review of the relationship between plasma concentrations and clinical response. Clin Pharmacokinet. 2007;46:359–388.
   PubMed Web of Science ®Google Scholar
• Patteet L, Morrens M, Maudens KE, et al. Therapeutic drug monitoring of common antipsychotics. Ther Drug Monit. 2012;34:629–651.
   PubMed Web of Science ®Google Scholar
• Lopez LV, Kane JM. Plasma levels of second-generation antipsychotics and clinical response in acute psychosis: a review of the literature. Schizophrenia Res. 2013;147:368–374.
   PubMed Web of Science ®Google Scholar
• Grundmann M, Kacirova I, Urinovska R. Therapeutic drug monitoring of atypical antipsychotic drugs. Acta Pharm. 2014;64:387–401.
   PubMed Web of Science ®Google Scholar
• de Leon J. Phenoconversion and therapeutic drug monitoring. Br J Clin Pharmacol. 2015;80:777–778.
   PubMed Web of Science ®Google Scholar
• Warner A. Setting standards of practice in therapeutic drug monitoring and clinical toxicology: a North American view. Ther Drug Monit. 2000;22:93–97.
   PubMed Web of Science ®Google Scholar
• Dahl ML, Sjöqvist F. Pharmacogenetic methods as a complement to therapeutic monitoring of antidepressants and neuroleptics. Ther Drug Monit. 2000;22:114–117.
   PubMed Web of Science ®Google Scholar
• Crettol S, de Leon J, Hiemke C, et al. Pharmacogenomics in psychiatry: from therapeutic drug monitoring to genomic medicine. Clin Pharmacol Ther. 2014;95:254–257.
   PubMed Web of Science ®Google Scholar
• Spina E, de Leon J. Clinical applications of CYP genotyping in psychiatry. J Neural Transm. 2015;122:5–28.
   PubMed Web of Science ®Google Scholar
• Shah RR, Smith RL. Addressing phenoconversion: the Achilles’ heel of personalized medicine. Br J Clin Pharmacol. 2015;79:222–240.
   PubMed Web of Science ®Google Scholar
• de Leon J. The crucial role of the therapeutic window in understanding the clinical relevance of the poor versus the ultrarapid metabolizer phenotypes in subjects taking drugs metabolized by CYP2D6 or CYP2C19. J Clin Psychopharmacol. 2007;27:241–245.
   PubMed Web of Science ®Google Scholar
• Castberg I, Spigset O. Serum concentrations of risperidone and 9-hydroxyrisperidone after administration of the long-acting injectable form of risperidone: evidence from a routine therapeutic drug monitoring service. Ther Drug Monit. 2005;27:103–106.
   PubMed Web of Science ®Google Scholar
• Arvanitis LA, Miller BG. Multiple fixed doses of “Seroquel” (quetiapine) in patients with acute exacerbation of schizophrenia: a comparison with haloperidol and placebo. The Seroquel Trial 13 Study Group. Biol Psychiatry. 1997;42:233–246.
   PubMed Web of Science ®Google Scholar
• Urinovska R, Brozmanova H, Sistik P, et al. Liquid chromatography–tandem mass spectrometry method for determination of five antidepressants and four atypical antipsychotics and their main metabolites in human serum. J Chromatogr B. 2012;907:101–107.
   PubMed Web of Science ®Google Scholar
• Odom-White A, de Leon J. Clozapine levels and caffeine. J Clin Psychiatry. 1996;57:175–176.
   PubMed Web of Science ®Google Scholar
• Lane HY, Su KP, Chang WH, et al. Elevated plasma clozapine concentrations after phenobarbital discontinuation. J Clin Psychiatry. 1998;59:131–133.
   PubMed Web of Science ®Google Scholar
• Hiemke C, Weigmann H, Härtter S, et al. Elevated levels of clozapine in serum after addition of fluvoxamine. J Clin Psychopharmacol. 1994;14:279–281.
   PubMed Web of Science ®Google Scholar
• Szegedi A, Wiesner J, Hiemke C. Improved efficacy and fewer side effects under clozapine treatment after addition of fluvoxamine. J Clin Psychopharmacol. 1995;15:141–143.
   PubMed Web of Science ®Google Scholar
• Markowitz JS, Gill HS, DeVane CL, et al. Fluoroquinolone inhibition of clozapine metabolism. Am J Psychiatry. 1997;153:881.
   Google Scholar
• Sanbhi R, Purl R, Jones G. Interaction of clozapine and ciprofloxacin: a case report. Eur J Clin Pharmacol. 2007;63:895–896.
   PubMed Web of Science ®Google Scholar
• Brouwers EEM, Sohne M, Kuipers S, et al. Ciprofloxacin strongly inhibits clozapine metabolism. Clin Drug Invest. 2009;29:59–63.
   PubMed Web of Science ®Google Scholar
• Funderberg LG, Vertrees JE, True JE, et al. Seizure following addition of erythromycin to clozapine treatment. Am J Psychiatry. 1994;151:1840–1841.
   Web of Science ®Google Scholar
• Joos AAB, Frank UG, Kaschka WP. Pharmacokinetic interaction of clozapine and rifampicin in a forensic patient with an atypical mycobacterial infection. J Clin Psychopharmacol. 1998;18:83–85.
   PubMed Web of Science ®Google Scholar
• Frick A, Kopitz J, Bergemann N. Omeprazole reduces clozapine plasma concentrations. Pharmacopsychiatry. 2008;36:121–123.
   Google Scholar
• Bork JA, Rogers T, Wedlund PJ, et al. A pilot study on risperidone metabolism: the role of cytochromes P450 2D6 and 3A. J Clin Psychiatry. 1999;60:469–476.
   PubMed Web of Science ®Google Scholar
• de Leon J, Bork J. Risperidone and cytochrome P4503A. J Clin Psychiatry. 1997;58:450.
   PubMed Web of Science ®Google Scholar
• Spina E, Scordo MG, Avenoso A, et al. Adverse drug interaction between risperidone and carbamazepine in a patient with chronic schizophrenia and deficient CYP2D6 activity. J Clin Psychopharmacol. 2001;21:108–109.
   PubMed Web of Science ®Google Scholar
• Markowitz JS, Devane CL. Suspected ciprofloxacin inhibition of olanzapine resulting in increased plasma concentrations. J Clin Psychopharmacol. 1999;19:289–291.
   PubMed Web of Science ®Google Scholar
• Licht RW, Olesen OV, Friis P, et al. Olanzapine serum concentrations lowered by concomitant treatment with carbamazepine. J Clin Psychopharmacol. 2000;20:110–112.
   PubMed Web of Science ®Google Scholar
• Pollack TM, McCoy C, Stead W. Clinically significant adverse events from a drug interaction between quetiapine and atazanavir–ritonavir in two patients. Pharmacotherapy. 2009;29:1386–1391.
   PubMed Web of Science ®Google Scholar
• McGrane IR, Loveland JG, Zaluski HJ, et al. Serum quetiapine concentration changes with concomitant oxcarbazepine therapy in a boy with autism spectrum disorder. J Child Adolesc Psychopharmacol. 2015;25:729–730.
   PubMed Web of Science ®Google Scholar
• Aung GL, O’Brien JG, Tien PG, et al. Increased aripiprazole concentrations in an HIV-positive male concurrently taking duloxetine, darunavir, and ritonavir. Ann Pharmacother. 2010;44:1850–1854.
   PubMed Web of Science ®Google Scholar
• Wetzel H, Anghelescu I, Szegedi A, et al. Pharmacokinetic interactions of clozapine with selective serotonin reuptake inhibitors: differential effects of fluvoxamine and paroxetine in a prospective study. J Clin Psychopharmacol. 1998;18:2–9.
   PubMed Web of Science ®Google Scholar
• Spina E, Avenoso A, Facciolà G, et al. Effect of fluoxetine on the plasma concentrations of clozapine and its major metabolites in patients with schizophrenia. Int Clin Psychopharmacol. 1998;13:141–145.
   PubMed Web of Science ®Google Scholar
• Spina E, Avenoso A, Facciolà G, et al. Plasma concentrations of risperidone and 9-hydroxyrisperidone: effect of comedication with carbamazepine or valproate. Ther Drug Monit. 2000;22:481–485.
   PubMed Web of Science ®Google Scholar
• Spina E, Avenoso A, Facciolà G, et al. Plasma concentrations of risperidone and 9-hydroxyrisperidone during combined treatment with paroxetine. Ther Drug Monit. 2001;23:223–227.
   PubMed Web of Science ®Google Scholar
• Saito M, Yasui-Furukori N, Nakagami T, et al. Dose-dependent interaction of paroxetine with risperidone in schizophrenic patients. J Clin Psychopharmacol. 2005;25:527–532.
   PubMed Web of Science ®Google Scholar
• Nakamura A, Mihara K, Nagai G, et al. Pharmacokinetic and pharmacodynamic interactions between carbamazepine and aripiprazole in patients with schizophrenia. Ther Drug Monit. 2009;31:575–578.
   PubMed Web of Science ®Google Scholar
• Nemoto K, Mihara K, Nakamura A, et al. Effects of paroxetine on plasma concentrations of aripiprazole and its active metabolite, dehydroaripiprazole, in Japanese patients with schizophrenia. Ther Drug Monit. 2012;34:188–192.
   PubMed Web of Science ®Google Scholar
• Yasui-Furukori N, Kubo K, Ishioka M, et al. Interaction between paliperidone and carbamazepine. Ther Drug Monit. 2013;35:649–652.
   PubMed Web of Science ®Google Scholar
• de Leon J, Wynn G, Sandson NB. The pharmacokinetics of paliperidone versus risperidone. Psychosomatics. 2010;51:80–88.
   PubMed Web of Science ®Google Scholar
• Kerbusch-Herben V, Cleton A, Berwaets J, et al. Effect of carbamazepine on the pharmacokinetics of paliperidone extended-release tablets at steady state. Clin Pharmacol Drug Develop. 2014;20:1–7.
   Google Scholar
• de Leon J. The effects of antiepileptic inducers in neuropsychopharmacology, a neglected issue. Part I: a summary of the current state for clinicians. Rev Psiquiatr Salud Ment. 2015;8:97–115.
   PubMed Web of Science ®Google Scholar
• Jaquenoud Sirot E, Knezevic B, Morena GP, et al. ABCB1 and cytochrome P450 polymorphisms: clinical pharmacogenetics of clozapine. J Clin Psychopharmacol. 2009;29:319–326.
   PubMed Web of Science ®Google Scholar
• Greenwood-Smith C, Lubman DI, Castle DJ. Serum clozapine levels: a review of their clinical utility. J Psychopharmacol. 2003;17:234–238.
   PubMed Web of Science ®Google Scholar
• Jerling M, Lindstrom L, Bondesson U, et al. Fluvoxamine inhibition and carbamazepine induction of the metabolism of clozapine: evidence from a therapeutic drug monitoring service. Ther Drug Monit. 1994;16:368–374.
   PubMed Web of Science ®Google Scholar
• Szegedi A, Anghelescu I, Wiesner J, et al. Addition of low-dose of fluvoxamine to low-dose clozapine monotherapy in schizophrenia: drug monitoring and tolerability data from a prospective clinical trial. Pharmacopsychiatry. 1999;32:148–153.
   PubMed Web of Science ®Google Scholar
• Diaz FJ, Santoro V, Spina E, et al. Estimating the size of the effects of co-medications on plasma clozapine concentrations using a model that controls for clozapine doses and confounding variables. Pharmacopsychiatry. 2008;41:81–91.
   PubMed Web of Science ®Google Scholar
• Diaz FJ, Rivera T, Josiassen R, et al. Individualizing drug dosage by using a random intercept linear model. Stat Med. 2007;26:2052–2073.
   PubMed Web of Science ®Google Scholar
• Facciolà G, Avenoso A, Spina E, et al. Inducing effect of phenobarbital on clozapine metabolism in patients with chronic schizophrenia. Ther Drug Monit. 1998;20:628–630.
   PubMed Web of Science ®Google Scholar
• Facciolà G, Avenoso A, Scordo MG, et al. Small effects of valproic acid on the plasma concentrations of clozapine and its major metabolites in patients with schizophrenic or affective disorders. Ther Drug Monit. 1999;21:341–345.
   PubMed Web of Science ®Google Scholar
• Spina E, Avenoso A, Salemi M, et al. Plasma concentrations of clozapine and its major metabolites during combined treatment with paroxetine or sertraline. Pharmacopsychiatry. 2000;33:213–217.
   PubMed Web of Science ®Google Scholar
• Avenoso A, Facciolà G, Scordo MG, et al. No effect of citalopram on plasma concentrations of clozapine, risperidone and their active metabolites in patients with chronic schizophrenia. Clin Drug Invest. 1998;16:393–398.
   Web of Science ®Google Scholar
• Spina E, Avenoso A, Scordo MG, et al. No effect of reboxetine on plasma concentrations of clozapine, risperidone and their active metabolites. Ther Drug Monit. 2001;23:675–678.
   PubMed Web of Science ®Google Scholar
• Seto K, Dumontet J, Ensom MHH. Risperidone in schizophrenia: is there a role for therapeutic drug monitoring? Ther Drug Monit. 2011;33:275–283.
   PubMed Web of Science ®Google Scholar
• Mannheimer B, von Bahr C, Pettersson H, et al. Impact of multiple inhibitors or substrates of cytochrome P450 2D6 on plasma risperidone levels in patients on polypharmacy. Ther Drug Monit. 2008;30:565–569.
   PubMed Web of Science ®Google Scholar
• de Leon J, Susce MT, Pan RM, et al. A study of genetic (CYP2D6 and ABCB1) and environmental (drug inhibitors and inducers) variables that may influence plasma risperidone levels. Pharmacopsychiatry. 2007;40:93–102.
   PubMed Web of Science ®Google Scholar
• Schwenger E, Dumontet J, Ensom MHH. Does olanzapine warrant clinical pharmacokinetic monitoring in schizophrenia? Clin Pharmacokinet. 2011;50:415–428.
   PubMed Web of Science ®Google Scholar
• Olesen OV, Linnet K. Olanzapine serum concentrations in psychiatric patients given standard doses: the influence of comedication. Ther Drug Monit. 1999;21:87–90.
   PubMed Web of Science ®Google Scholar
• Linnet K, Olesen OV. Free and glucuronidated olanzapine serum concentrations in psychiatric patients: influence of carbamazepine comedication. Ther Drug Monit. 2002;24:512–517.
   PubMed Web of Science ®Google Scholar
• Weigmann H, Gerek S, Zeisig A, et al. Fluvoxamine but not sertraline inhibits the metabolism of olanzapine: evidence from a therapeutic drug monitoring service. Ther Drug Monit. 2001;23:410–413.
   PubMed Web of Science ®Google Scholar
• Skogh E, Reis M, Dahl M, et al. Therapeutic drug monitoring data on olanzapine and its N-demethyl metabolite in the naturalistic clinical setting. Ther Drug Monit. 2002;24:518–526.
   PubMed Web of Science ®Google Scholar
• Gex-Fabry M, Balant-Gorgia AE, Balant LP. Therapeutic drug monitoring of olanzapine: the combined effect of age, gender, smoking, and comedication. Ther Drug Monit. 2003;25:46–53.
   PubMed Web of Science ®Google Scholar
• Botts S, Diaz FJ, Santoro V, et al. Estimating the effects of co-medications on plasma olanzapine concentrations by using a mixed model. Progr Neuro-Psychopharmacol Biol Psychiat. 2008;32:1453–1458.
   PubMed Web of Science ®Google Scholar
• Spina E, D’Arrigo C, Migliardi G, et al. Effect of adjunctive lamotrigine treatment on the plasma concentrations of clozapine, risperidone and olanzapine in patients with schizophrenia or bipolar disorder. Ther Drug Monit. 2006;28:599–602.
   PubMed Web of Science ®Google Scholar
• Muscatello RM, Pacetti M, Cacciola M, et al. Plasma concentrations of risperidone and olanzapine during coadministration with oxcarbazepine. Epilepsia. 2005;46:771–774.
   PubMed Web of Science ®Google Scholar
• Migliardi G, D’Arrigo C, Santoro V, et al. Effect of topiramate on plasma concentrations of clozapine, olanzapine, risperidone, and quetiapine in patients with psychotic disorders. Clin Neuropharmacol. 2007;30:107–113.
   PubMed Web of Science ®Google Scholar
• Zoccali R, Muscatello MR, La Torre D, et al. Lack of a pharmacokinetic interaction between mirtazapine and the newer antipsychotics clozapine, risperidone and olanzapine in patients with chronic schizophrenia. Pharmacol Res. 2003;48:411–414.
   PubMed Web of Science ®Google Scholar
• Haslemo T, Refsum H, Molden E. The effect of ethinylestradiol-containing contraceptives on the serum concentration of olanzapine and N-desmethyl olanzapine. Br J Clin Pharmacol. 2011;71:611–615.
   PubMed Web of Science ®Google Scholar
• Haslemo T, Olsen K, Lunde H, et al. Valproic acid significantly lowers serum concentrations of olanzapine. An interaction effect comparable with smoking. Ther Drug Monit. 2012;34:512–517.
   PubMed Web of Science ®Google Scholar
• Hasselstrøm J, Linnet K. Quetiapine serum concentrations in psychiatric patients: the influence of comedication. Ther Drug Monit. 2004;26:486–491.
   PubMed Web of Science ®Google Scholar
• Aichhorn W, Marksteiner J, Walch T, et al. Influence of age, gender, body weight and valproate comedication on quetiapine plasma concentrations. Int Clin Psychopharmacol. 2006;21:81–85.
   PubMed Web of Science ®Google Scholar
• Castberg I, Skogvoll E, Spigset O. Quetiapine and drug interactions: evidence from a routine therapeutic drug monitoring service. J Clin Psychiatry. 2007;68:1540–1545.
   PubMed Web of Science ®Google Scholar
• Santoro V, D’Arrigo C, Migliardi G, et al. Therapeutic drug monitoring of quetiapine: effect of coadministration with antiepileptic drugs in patients with psychiatric disorders. Open Clin Chem J. 2008;1:17–21.
   Google Scholar
• Andersson ML, Björkhem-Bergman L, Lindh JD. Possible drug–drug interaction between quetiapine and lamotrigine – evidence from a Swedish TDM database. Br J Clin Pharmacol. 2011;72:153–156.
   PubMed Web of Science ®Google Scholar
• Bakken GV, Rudberg I, Molden E, et al. Pharmacokinetic variability of quetiapine and the active metabolite N-desalkylquetiapine in psychiatric patients. Ther Drug Monit. 2011;33:222–226.
   PubMed Web of Science ®Google Scholar
• Molden E, Lunde H, Lunder N, et al. Pharmacokinetic variability of aripiprazole and the active metabolite dehydroaripiprazole in psychiatric patients. Ther Drug Monit. 2006;28:744–749.
   PubMed Web of Science ®Google Scholar
• Castberg I, Spigset O. Effects of comedication on the serum levels of aripiprazole: evidence from a routine therapeutic drug monitoring service. Pharmacopsychiatry. 2007;40:107–110.
   PubMed Web of Science ®Google Scholar
• Waade RB, Christensen H, Rudberg I, et al. Influence of comedication on serum concentrations of aripiprazole and dehydroaripiprazole. Ther Drug Monit. 2009;31:233–238.
   PubMed Web of Science ®Google Scholar
• Cherma MD, Reis M, Hagg S, et al. Therapeutic drug monitoring of ziprasidone in a clinical setting. Ther Drug Monitor. 2008;30:682–688.
   PubMed Web of Science ®Google Scholar
• Vogel F, Gansmüller R, Leiblein T, et al. The use of ziprasidone in clinical practice: analysis of pharmacokinetic and pharmacodynamic aspects from data of a drug monitoring survey. Eur Psychiatry. 2009;24:143–148.
   PubMed Web of Science ®Google Scholar
• Miceli JJ, Anziano RJ, Robarge L, et al. The effect of carbamazepine on the steady-state pharmacokinetics of ziprasidone in healthy volunteers. Br J Clin Pharmacol. 2000;49(Suppl 1):65S–70S.
   PubMed Web of Science ®Google Scholar
• Bowskill SVJ, Patel MX, Handley SA, et al. Plasma amisulpride in relation to prescribed dose, clozapine augmentation, and other factors: data from a therapeutic drug monitoring service, 2002–2010. Hum Psychopharmacol Clin Exp. 2012;27:507–513.
   PubMed Web of Science ®Google Scholar
• de Leon J. Highlights of drug package inserts and the website DailyMed: the need for further improvement in package inserts to help busy prescribers. J Clin Psychopharmacol. 2011;31:263–265.
   PubMed Web of Science ®Google Scholar
• de Leon J, Spina E, Diaz FJ. Pharmacokinetic drug interaction studies must consider pharmacological heterogeneity, use of repeated dosing, and translation into a message understandable to practicing clinicians. J Clin Psychopharmacol. 2009;29:201–205.
   PubMed Web of Science ®Google Scholar
• Riesselman A, Strobl B, Cooley AT, et al. A case report that suggested that aspirin’s effects on valproic acid metabolism may contribute to valproic acid’s inducer effects on clozapine metabolism. J Clin Psychopharmacol. 2013;33:812–814.
   PubMed Web of Science ®Google Scholar
• de Leon J, Sandson NB, Cozza KL. A preliminary attempt to personalize risperidone dosing using drug-drug interactions and genetics: part II. Psychosomatics. 2008;49:347–361.
   PubMed Web of Science ®Google Scholar
• de Leon J. Atypical antipsychotic dosing: the effect of smoking and caffeine. Psychiatr Serv. 2004;55:491–493.
   PubMed Web of Science ®Google Scholar
• de Leon J, Diaz FJ. Serious respiratory infections can increase clozapine levels and contribute to side effects: a case report. Prog Neuropsychopharmacol Biol Psychiatry. 2003;27:1059–1063.
   PubMed Web of Science ®Google Scholar
• Shah RR, Smith RL. Inflammation-induced phenoconversion of polymorphic drug metabolizing enzymes: hypothesis with implications for personalized medicine. Drug Metab Dispos. 2015;43:400–410.
   PubMed Web of Science ®Google Scholar
• Hefner G, Falter T, Bruns K, et al. Elevated risperidone serum concentrations during acute inflammation, two cases. Int J Psychiatry Med. 2015;50:335–344.
   PubMed Web of Science ®Google Scholar
• Hefner G, Shams ME, Unterecker S, et al. Inflammation and psychotropic drugs: the relationship between C-reactive protein and antipsychotic drug levels. Psychopharmacology (Berl). 2015 Jun 3. [Epub ahead of print].
   PubMedGoogle Scholar
• Pfuhlmann B, Hiemke C, Unterecker S, et al. Toxic clozapine serum levels during inflammatory reactions. J Clin Psychopharmacol. 2009;29:392–394.
   PubMed Web of Science ®Google Scholar
• Citrome L, Josiassen R, Bark N, et al. Pharmacokinetics of aripiprazole and concomitant lithium and valproate. J Clin Pharmacol. 2005;45:89–93.
   PubMed Web of Science ®Google Scholar