TPMT genotype and the response to azathioprine in inflammatory bowel disease: authors’ reply

but in a clinical response to a median dose lower than that used in patients with a normal TPMT gene (1.6 mg ⁄ kg ⁄ day vs. 2.2 mg ⁄ kg ⁄ day). The treatment with azathioprine at high doses (3.0 mg ⁄ kg ⁄ day) is safe and in our experience particularly effective for patients with a wild-type TPMT genotype. 7 TPMT genotyping could therefore be useful to obtain a better clinical response, with a starting dose of azathioprine tailored according to the patient genotype. 8

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