Toxicity and/or insufficient analgesia by opioid therapy: risk factors and the impact of changing the opioid. A retrospective analysis of 273 patients observed at a single center
Kloke M, Rapp M, Bosse B, Kloke O
Department of Internal Medicine (Cancer Research),
University of Essen,
Medical School, Germany.
Support Care Cancer 2000 Nov; 8(6):479-86 1999 Sep;124(1):51-5


The charts of 273 cancer patients were retrospectively analyzed in order (1) to evaluate the frequency of opioid change (OCH) when adjuvants (antiemetics/laxatives) were administered on a regular basis and co-analgesic medication as indicated by the specific type of pain, (2) to define risk factors for the request of OCH, and (3) to reveal settings in which OCH may not be recommended as a first-line therapeutic intervention. Opioids used included morphine, fentanyl, 1-methadone, and buprenorphine. Out of 273 patients, 103 changed opioids at least once, with a success rate of 65%. The indications for the OCH were insufficient analgesia in 43%, intolerable side effects in 20%, both in 15%, and other reasons in 22% of patients. The frequency of OCH was not influenced by the routine use of adjuvants or co-analgesics except corticosteroids, which raises queries about the concept of an opioid-sparing effect of co-analgesics. The occurrence of intolerable side effects is thought not to be dose dependent so much as to reflect differences in the individual tolerability of a distinct opioid for whatever reason (genetically fixed or individually acquired pharmacodynamic or kinetic properties). Moreover, there was strong evidence for the existence of an unpredictable and incomplete cross-tolerance between opioids, which meant careful titration of the new opioid was required after OCH. The overall frequency of OCH was similar to that observed in previous studies in spite of the documented addition of adjuvants and co-analgesics. This retrospective study supports the notion that opioid rotation must be retained as an essential therapeutic option even with optimized adjuvant and co-analgesic regimens.
Why itch?
Morphine worms
Opiated crickets
Novelty and pain
Discounting rewards
Fentanyl and ketamine
Opioids, mood and cognition
Opioids, dopamine and alcohol
Opioids, goldfish and the giant toad
Heroin, cocaine and the squirrel monkey

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Future Opioids
BLTC Research
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World

The Good Drug Guide
The Good Drug Guide

The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family