Methadone patients who are on a blocking dose (80 mgs and above) feel nothing at all from other opioid drugs. They get NO high, NO euphoria whatsoever, thus no reason to pursue them. Most patients ARE in the 80-120 mg dose range and so are blockaded.

Methadone patients in acute pain should be treated with larger than normal doses of opioid drugs and briefer intervals than normal patients, due to their massive tolerance.  Many doctors make the serious mistake of assuming that mathadone pts don't need any form of pain relief because they are already on methadone--however, chronic methadone patients who take methadone once daily get no pain relieving effects from their dose--they are tolerant to it. Due to this, doses of a medication that might kill a person unused to opioids may be required to even minimally control severe pain in these patients.