Related Experiment Video
Updated: Jun 10, 2026

Quantification of the Immunosuppressant Tacrolimus on Dried Blood Spots Using LC-MS/MS
Published on: November 8, 2015
[Therapeutic drug monitoring of methotrexate after its administration in high-dose protocols]
Chantal Le Guellec1, Hélène Blasco, Isabelle Benz
1Unité de Pharmacogénétique, Université François Rabelais de Tours, CHRU de Tours, France. leguellec@med.univ-tours.fr
Abstract:
After HD-MTX infusions, i.e. at a dose>1 g/m2, monitoring of serum MTX concentrations is a standard practice which helps reducing the incidence of toxicity in patients with decreased clearance by guiding dose adjustment of leucovorin. Therapeutic monitoring of methotrexate is based on iterative measurements of serum concentration until concentration is below a certain threshold. This practice is supported by numerous observations of exposure-related toxicity as well as some clinical studies comparing drug exposure between patients with and without toxicity. Despite no prospective clinical study has clearly demonstrated the usefulness of methotrexate TDM, historical comparison reveals a huge reduction of toxicity-related events over past decades. Systematic monitoring may also help identifying patients with abnormally high methotrexate concentrations, who require immediate treatment with carboxypeptidase.
Related Concept Videos
Therapeutic Drug Monitoring: Affecting Factors
Therapeutic Drug Monitoring: Overview and Classification
Therapeutic Drug Monitoring: Drug Analysis Methods
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Dosage Regimens: Designs and Approaches
Drugs for Treatment of Crohn's Disease in IBD Using Immunomodulatory Agents
