Table 1.

Search strategy

Search strategy in Embase for drug–drug interactions (DDIs) involving opioid analgesics used for pain treatment in cancer patients (#1 or #2 or #3)
#1 (exp opiate agonist/it or exp narcotic analgesic agent/it or exp narcotic agent/it or exp morphine derivative/it) and exp neoplasm/
#2 (exp opiate agonist/or exp narcotic analgesic agent/or exp narcotic agent/or exp morphine derivative/) and exp neoplasm/and (drug interaction/or drug antagonism/or drug competition/or drug inhibition/or drug potentiation/) and (exp pain/or analgesia/or analgesic activity/or pain relief/)
#3 (exp opiate agonist/or exp narcotic analgesic agent/or exp narcotic agent/or exp morphine derivative/) and exp neoplasm/and polypharmacy/