Therapeutic drug monitoring in neuropsychopharmacology: does it hold its promises?

Full Abstract

To produce its characteristic effects, a drug must be present in appropriate concentrations at its sites of action. The latter is not only a function of the dose administered, but also of the extent and rate of drug absorption, distribution, tissue binding, biotransformation, and excretion, which can vary markedly between individual patients due to differences in gender, age, morbidity, smoking or eating habits, differential expression of drug metabolising enzymes or drug transporters or other factors. Therefore drug concentrations in blood resulting after a given dose differ by tenfold or more between individual patients. For psychoactive drugs, animal studies have shown that plasma concentrations of psychotropic drugs correlate well with concentrations in the target organ, the brain. In the brain of patients treated with antipsychotic or antidepressant drugs clear-cut relationships were found between plasma concentrations of the drug and occupancy of dopamine receptors or serotonin uptake sites by positron emission tomography (PET). Monitoring concentrations of psychoactive drugs in plasma of patients, so called therapeutic drug monitoring (TDM), is therefore useful to adjust dosages for optimal "receptor" blockade. TDM is well established for mood stabilizers and anticonvulsant drugs. For other neuropsychiatric drugs, however, "routine" TDM is rare. Optimal target concentrations are unclear for many drugs, and the number of laboratories that use reliable methods to measure the low concentrations of the drugs within a single day is quite limited. Moreover, the use of TDM in practice is far from optimal. The TDM group of the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (AGNP see http://www.agnp.de/) has published literature-based guidelines for optimal use of TDM in psychiatry. TDM can be most informative to solve problems underlying the treatment of an individual patient. It can be clarified if suggested non-compliance or insufficient response in spite of recommended doses is due to rapid metabolism of the drug. Moreover, many drug interactions have been detected by using TDM. In conclusion, TDM is a reliable tool to optimise psychopharmacotherapy. When used adequately it is helpful for many psychiatric patients and in many situations.

Learn Faster Today Improve your study skills

Author information

Author/s: Hiemke, Christoph (C);

Affiliation: Department of Psychiatry, University of Mainz, Untere Zahlbacher Str 8, Mainz, Germany. hiemke(-atsign-)mail.uni-mainz.de

Journal and publication information

Publication Type: Journal Article; Review

Journal: European archives of psychiatry and clinical neuroscience (Eur Arch Psychiatry Clin Neurosci), published in Germany. (Language: eng)

Reference: 2008-Mar; vol 258 Suppl 1 (issue ) : pp 21-7

Dates: Created 2008/03/17; Completed 2008/05/06;

PMID: 18344046, status: MEDLINE (last retrieval date: 11/6/2008)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article (including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.

MeSH headings (categories)

This article was linked to the MESH Headings shown below.

Dose-Response Relationship, Drug
Drug Monitoring - trends
Guidelines as Topic
Humans

Mental Disorders - drug therapy; metabolism
Neuropsychology - trends
Psychopharmacology - trends
Psychotropic Drugs - administration & dosage; pharmacokinetics; therapeutic use

Associated Chemicals: Psychotropic Drugs (0)

These are the highest related articles currently in the database:

See 100+ related articles.