CHAPTER 3: PHARMACOLOGIC MANAGEMENT

Recommendations

13. An essential principle in using medications to manage cancer pain is to individualize the regimen to the patient. (A) 14. The simplest dosage schedules and least invasive pain management modalities should be used first. (Panel Consensus) 15. Pharmacologic management of mild to moderate cancer pain should include an NSAID or acetaminophen, unless there is a contraindication. (A) 16. When pain persists or increases, an opioid should be added. (A) 17. Treatment of persistent or moderate to severe pain should be based on increasing the opioid potency or dose. (A) 18. Medications for persistent cancer-related pain should be administered on an around-the-clock basis with additional "as-needed" doses, because regularly scheduled dosing maintains a constant level of drug in the body and helps to prevent a recurrence of pain. (A) 19. Patients receiving opioid agonists should not be given a mixed agonist-antagonist because doing so may precipitate a withdrawal syndrome and increase pain. (B) 20. Meperidine should not be used if continued opioid use is anticipated. (B) 21. Opioid tolerance and physical dependence are expected with long-term opioid treatment and should not be confused with addiction. (Panel Consensus) 22. The oral route is the preferred route of analgesic administration because it is the most convenient and cost-effective method of administration. When patients cannot take medications orally, rectal and transdermal routes should be considered because they are also relatively noninvasive. (Panel Consensus) 23. Intramuscular administration of drugs should be avoided because this route can be painful and inconvenient, and absorption is not reliable. (B) 24. Failure of maximal systemic doses of opioids and coanalgesics should precede the consideration of intraspinal analgesic systems. (Panel Consensus) 25. Because there is great interindividual variation in susceptibility to opioid-induced side effects, clinicians should monitor for these potential side effects. (B) 26. Constipation is a common problem associated with long-term opioid administration and should be anticipated, treated prophylactically, and monitored constantly. (B) 27. Naloxone, when indicated for reversal o[[sterling]]-opioid-induced respiratory depression, should be titrated in doses that improve respiratory function but do not reverse analgesia. (B) 28. Placebos should not be used in the management of cancer pain. (Panel Consensus) 29. Patients should be given a written pain management plan. (A) 30. Communication about pain,management should occur when a patient is transferred from one setting to another. (B) Drug therapy is the cornerstone of the many modalities available to manage cancer pain because it is effective, relatively low risk, inexpensive, and usually of rapid onset. An essential principle in using medications-to manage cancer pain is to individualize the regimen to the patient (Foley, 1985a).

Three major classes of drugs are used alone or, more commonly, in combination to manage pain in the cancer patient:

NSAIDs and acetaminophen (APAP). Opioid analgesics. Adjuvant analgesics.

Before choosing drugs to manage pain or other symptoms, identify the specific cause(s) of the pain, evaluate its intensity and quality, and then match the drug to the pain intensity and other characteristics. The simplest dosage schedules and least invasive pain management modalities should be used first. After drug therapy has been started, pain should be assessed to determine the ongoing effectiveness of the analgesic therapy. For opioid analgesics, if pain relief is inadequate, the dose should be increased until pain relief is achieved or unacceptable side effects occur. In the case of NSAIDS and adjutant analgesic drugs, which have ceiling effects to their analgesic efficacy, if the upper limit of the recommended dose is reached and pain relief is not achieved, then that particular drug should be discontinued and a second drug in that class should be used.

Most cancer pain can be managed by oral administration of drugs; however, difficulty in swallowing, gastrointestinal (GI) disturbances that render drug absorption unreliable, the amount of drug required, and many other factors may require alternative routes of administration (Coyle, Adelhardt, Foley, et al., 1990; Grond, Zech, Schug, et al., 1991). Table 8 summarizes some of the advantages and disadvantages of cancer pain therapies.


Related Chunks

The WHO Ladder

Dosage Titration

Transdermal

Nasal

Figure 2: The WHO Ladder

Dose Equivalence Table for Opioid Analgesics in Opioid-naive Adults and Children greater than or equal to 50kg body weight.

Dose Equivalence Table for Opioid Analgesics in Opioid-naive Adults and Children less than 50kg body weight.

Under development

Index