The aim of this study was to determine by consensus the components of an opioid essential prescription package (OEPP) to be used when initiating a prescription for the control of moderate to severe chronic pain. Palliative care physicians (n=60) were sampled from the International Association for Hospice and Palliative Care (IAHPC) membership list to represent a range of countries of varying economic levels and diverse geographical regions. Using a Delphi study method, physicians were asked to rank preferences of drug and dosing schedule for first-line opioid, antiemetic, and laxative for the treatment of adults with chronic pain due to cancer and other life-threatening conditions. Overall response rates after two Delphi survey rounds were 95% (n=57) and 82% (n=49), respectively. A consensus (set at ≥75% agreement) was reached to include morphine as first-line opioid at a dose of 5 mg orally every 4 hours. Consensus was reached to include metoclopramide as a first-line antiemetic, but there was no consensus on "regular" or "as needed" administration. No consensus was reached regarding a first-line laxative, but a combination of senna and docusate secured 59% agreement. There was consensus (93% agreement) that laxatives should always be given regularly when opioid treatment is started. Further work is needed to establish a recommended dose of metoclopramide and a type and dose of laxative. The resulting OEPP is international in scope and is designed to ensure that opioids are better tolerated by reducing adverse effects of opioids, which could lead to more sustained improvements in pain management.