Drugs are a relatively uncommon cause of pancreatitis in adult patients, but should be considered when other reasonable causes of pancreatitis are not present. A wide variety of drugs have been reported to cause pancreatitis. Drug-induced pancreatitis is almost always acute and may be mild to fatal in severity. Definite proof that a drug causes pancreatitis requires that pancreatitis develops during treatment with the drug, that other likely causes of pancreatitis are not present, that pancreatitis resolves upon discontinuing the drug, and that pancreatitis usually recurs upon readministration of the drug. For ethical reasons, rechallenge with the suspect drug can be done only if the drug is necessary to treat a serious condition; thus this highly convincing piece of evidence relating the drug to pancreatitis may not be available. Information about drug-related pancreatitis is often not readily available, particularly for newer drugs. Clinicians should consider obtaining information directly from regulatory agencies and manufacturers as well as the literature.