Psychotropics monitoring

Hendset, M. et al. 2006. The complexity of active metabolites in therapeutic drug monitoring of psychotropic drugs. Pharmacopsychiatry. 39 121. 

TABLE 4.2 Indications for Therapeutic Drug Monitoring of Psychotropic Drugs... 

Gex-Fabry, M., Balant-Gorgia, A.E., and Balant, L.P. (1997) Therapeutic drug monitoring databases for postmarketing surveillance of drug-drug interactions evaluation of a paired approach for psychotropic medication. Ther Drug Monit 19 1-10. 

Mitchell, P.B. (2000) Therapeutic drug monitoring of psychotropic medications. Br ] Clin Pharmacol 49 303-312. 

Gutgesell, H., Atkins, D., Barst, R., Buck, M., Franklin, W., Humes, R., Ringel, R., Shaddy, R., and Taubert, K. (1999) Cardiovascular monitoring of children and adolescents receiving psychotropic drugs. Circulation 99 979-982. 

The aims of this chapter are to (1) describe a contemporary approach to assessment for pharmacotherapy (2) describe clinical principles of pediatric psychopharmacology (3) describe clinical decision making in pediatric psychopharmacology and (4) describe current approaches to the medical monitoring of children treated with psychotropic medications. 

If psychotropic interventions are used, they should not be the only treatment strategy or model and the target symptomatolgy should be constantly monitored. 

Another use of the laboratory is for therapeutic drug monitoring (TDM) of psychotropics with defined optimal ranges, narrow therapeutic indices, or both. Although TDM is not essential for many psychotropics, it is for others, including lithium, several TCAs, valproate, and carbamazepine. It may also be helpful to optimize the use of certain antipsychotics (e.g., haloperidol, clozapine) ( 7). 

Plasma levels of various psychotropics differ widely among individuals on the same dose due to differences in their rates of metabolism. Therefore, the clinician must adjust each patient s dosage to achieve maximal benefit with minimal side effects. Therapeutic drug monitoring can be used to address these issues ... 

To monitor patients with other medical disorders or on concurrent psychotropics or other medical drugs... 

Although the overall response rate to VPA was 61 %, a number of methodological problems complicate the interpretation of these results, including that most patients were studied under nonblind conditions, this agent was often used in combination with other psychotropics, plasma concentrations were usually not monitored, and formal diagnostic criteria derived from standard clinical ratings were typically not used. 

Choong E, Rudaz S, Kottelat A et al (2009) Therapeutic drug monitoring of seven psychotropic drugs and four metabolites in human plasma by HPLC-MS. J Pharm Biomed Anal 50 1000-1008... 

In contrast, other authors have stated that serum concentration monitoring is recommended during maintenance treatment with clozapine, in the light of a retrospective, open, non-randomized study in 86 patients, in which 404 serum concentrations were measured (310). Eight cases of intoxication were identified, and the conclusions were that the risk of toxicity is increased at serum concentrations over 750 ng/ml, while the risk of relapse is low at serum concentrations over 250 ng/ml, irrespective of concurrent psychotropic drugs, although intoxication was defined only according to the reason for the request for serum concentrations assay, as outlined in the request form. 

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