Adjuncts to opioid therapy

Abstract

Administration of opioids to alleviate moderate to severe acute pain and chronic cancer pain is an established management process. However, advancements in clinical pharmacologic research have shown that opioids are also effective in chronic noncancerous pain. Many patients properly treated for prolonged periods with opioids develop tolerance and subsequently, physical dependence. This process is not necessarily harmful to the patient and will not cause the patient to develop an addiction (properly defined as psychologic dependence). For many patients who have been on opioid therapy for months or years, analgesic effectiveness tragically becomes less. In addition, opioid-induced constipation can be severe and cause pain; patients do not develop tolerance to this adverse reaction. Therefore, such issues become a management problem and require additional intervention. Currently, many different classes of drugs can serve as effective adjuncts to opioids for treatment of pain. Adding adjunctive medication to opioid therapy improves pain management primarily by nonopioid mechanisms of action. Clinical outcomes of such combinations include greater analgesia and attenuation of opioid-induced adverse reactions such as nausea and vomiting, constipation, sedation, and respiratory depression. Adjuncts include acetaminophen, antiarrhythmics, anticonvulsants, antidepressants, antipsychotics, baclofen, benzodiazepines, capsaicin, calcium channel blockers, clonidine hydrochloride, central nervous system stimulants, corticosteroids, local anesthetics, N-methyl-D-aspartate receptor antagonists, nonsteroidal antiinflammatory drugs, pentoxifylline, and scopolamine. Some adjuncts (eg, acetaminophen) are routinely used today, whereas others (eg, nifedipine [calcium channel blocker]) are used on a limited basis but have great potential for more widespread application. All professionals (eg, nurses, pharmacists, physicians, physicians' assistants, social workers, members of the clergy) involved in treating patients with unresolved pain recognize this to be an extraordinary and delicate time. It is when patients are likely to request physicians to provide some method to accelerate their death. Thus, inadequate analgesia can become a suicidogen, ie, any factor that causes a patient to want to commit suicide. Incorporation of adjuncts to opioid therapy can serve to lessen pain and improve quality of life for a suffering patient.