"Persons with substance use disorders are less likely than others to receive effective pain treatment (Rupp and Delaney, 2004). The primary reason is clinicians' concern that they may misuse opioids. Although mild to moderate pain can often be treated effectively with a combination of physical modalities (e.g., ice, rest, and splints) and nonopioid analgesics (e.g., nonsteroidal anti-inflammatory drugs [NSAIDs], acetaminophen, or other adjuvant medications), management of severe pain, especially when cancer-related, often requires opioids. Moreover, physicians are increasingly using opioids to treat chronic non-cancer-related pain, and an emerging body of evidence suggests that, for some patients, this approach both reduces pain and may foster modest improvements in function and quality of life (Devulder, Richarz, and Nataraja, 2005; Haythornthwaite et al., 1998; Kalso et al., 2004; Martell et al., 2007; Noble et al., 2008; Passik et al., 2005; Portenoy et al., 2007; Portenoy and Foley, 1986)."

Source

Savage, Seddon R., Kenneth L. Kirsh, and Steven D. Passik. "Challenges in Using Opioids to Treat Pain in Persons With Substance Use Disorders." Addiction Science & Clinical Practice 4.2 (2008): 4–25.
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