Naga P. Chalasani, MD, FACG, and Herbert L. Bonkovsky, MD, FACG, co-authors of the new ACG Clinical Guideline on drug-induced liver injury (DILI) talks with AJG Co-Editor Dr. William D. Chey about the definition of DILI and its different subtypes, risk factors for the disorder, the drug classes that pose the greatest risk of liver injury, and the essentials of clinical work-up for DILI patients, including when to perform a liver biopsy. Special note is paid to herbal and dietary supplements, which are largely unregulated and have caused increasing harm to patients over the past few years. (32:17)