When switching between opioids, equianalgesic conversions may overestimate the potency of the new opioid due to incomplete cross-tolerance. Incomplete cross-tolerance can occur due to variability in opioid binding. Opioid equivalent doses calculator. Opioid conversions based on equianalgesia -potency for all of the common opioids hydrocodone, oxycodone, morphine, etc Patch Conversion Rule: Fentanyl patches are appropriate only for opioid-tolerant patients (60 mg oral morphine/day equivalent for 1 week or more). Never use in opioid-naive patients. The half life of the two drugs needs to be considered when converting so that the patient does not experience breakthrough pain or receive too much opiate during the conversion period. Use caution when prescribing opioids at any dosage, and prescribe the lowest effective dose. Conversions are based on the CDC Clinical Practice Guideline for Prescribing Opioids for Pain — United States, 2022. The opioid conversion calculator tells you equivalent doses of analgesic drugs, such as morphine, fentanyl, or tramadol. Ideally, methadone conversions (especially patients who were previously receiving high doses of an opioid) should only be attempted in cooperation with a pain specialist or a specialist in palliative medicine. The Opiate Conversion Calculator converts between different types and routes of opiates. Opioid equivalence should NOT be used for opioid conversion. To do so is an inappropriate and potentially dangerous misunderstanding of the tool. Convert your patient’s opioid daily dose to the Morphine Equivalent Dose (MED) by using this online calculator.