Substance use disorders continue to be an important health issue in the United States and can lead to significant problems in all aspects of a person's life. Appropriate assessment and management of substance use is a priority in patient care.

Opioid analgesic medications can bring substantial relief to patients suffering from pain.

Opioid analgesics are approved by the FDA for the treatment of moderate or severe pain. However, individual patients differ greatly in clinical response to different opioid analgesics, and patient populations show widely variable response to the same opioid and dose.

Pain affects all domains of life, and clinicians have few effective tools at their disposal to help these patients. Opioids remain the strongest group of analgesic drugs available.