[Treatment of inflammatory bowel disease: what if drug therapy fails?].

The treatment of patients with chronic inflammatory bowel disease (IBD) in accordance with the current guideline is generally successful but there is still a group of patients for whom the medication does not work. If the initially prescribed medication is not sufficiently effective, the tendency is to move on to a 'higher' class of drugs relatively quickly. This is not always necessary. If therapy fails then therapy compliance and dosage should first be examined. Measurement of the metabolites of purine analogues can be helpful in determining the optimal drug dosage. The results sometimes show that a previously-prescribed drug may still be an option. Despite its proven efficacy, methotrexate appears to be being prescribed less often. For those patients who do not respond adequately to the optimum dosage of anti-tumour necrosis factor (TNF), there are new drugs on the way. Vedolizumab, a leukocyte adhesion inhibitor, in particular is showing promising results.