Therapeutic Drug Monitoring in Inflammatory Bowel Disease

Publication Date: September 1, 2017
Last Updated: December 16, 2022

Treatment

In adults with active IBD treated with anti-TNF agents, AGA suggests reactive therapeutic drug monitoring to guide treatment changes.
Comment: Table 1 summarizes suggested trough concentration for anti-TNF therapy for patients with active IBD on maintenance therapy. Of note, there may be a small subset of patients who may respond to higher target concentrations. Optimal trough concentrations for induction therapy are uncertain.
612
In adult patients with quiescent IBD treated with anti-TNF agents, AGA makes no recommendation regarding the use of routine proactive therapeutic drug monitoring.
612
In adult patients with IBD being started on thiopurines, AGA suggests routine thiopurine methyltransferase (TPMT) testing (enzymatic activity or genotype) to guide thiopurine dosing. (Low, Conditional (weak))
Comment: Routine laboratory monitoring, including CBC, should be performed, regardless of TPMT testing results.
612
In adult patients treated with thiopurines with active IBD or adverse effects thought to be due to thiopurine toxicity, AGA suggests reactive thiopurine metabolite monitoring to guide treatment changes.
Comment: When measuring thiopurine metabolite monitoring in patients with active IBD-related symptoms, we suggest a target 6-thioguanine (6-TGN) cutoff between 230–450 pmol/8 × 108 RBCs when used as monotherapy. Optimal 6-TGN cutoff when thiopurines are used in combination with anti-TNF agents is uncertain.
612
In adult patients with quiescent IBD treated with thiopurines, AGA suggests against routine thiopurine metabolite monitoring.
612

Recommendation Grading

Overview

Title

Therapeutic Drug Monitoring in Inflammatory Bowel Disease

Authoring Organization

American Gastroenterological Association

Publication Month/Year

September 1, 2017

Last Updated Month/Year

November 6, 2024

Document Type

Guideline

External Publication Status

Published

Country of Publication

US

Document Objectives

This document presents the official recommendations of the American Gastroenterological Association (AGA) on therapeutic drug monitoring (TDM) in inflammatory bowel disease (IBD).

Target Patient Population

Adults with active IBD

Inclusion Criteria

Male, Female, Adult, Older adult

Health Care Settings

Ambulatory

Intended Users

Nurse, nurse practitioner, physician, physician assistant

Scope

Assessment and screening, Management

Diseases/Conditions (MeSH)

D015212 - Inflammatory Bowel Diseases, D016903 - Drug Monitoring

Keywords

inflammatory bowel disease, ulcerative colitis, Crohn's disease, IBD, therapeutic drug monitoring

Source Citation

Feuerstein JD et al. Therapeutic Drug Monitoring in Inflammatory Bowel Disease. Gastroenterology. 2017 Sep;153(3):827-834.

Supplemental Methodology Resources

Technical Review