The abuse of prescription-controlled substances is a common phenomenon, associated with illicit drug use, in patients suffering with chronic pain and receiving controlled substances for the management of pain. Prescription drug abuse in Kentucky has led to an increase in Medicare and Medicaid fraud, as well as physician indictments for unscrupulous practices and increased vigilance and prosecution by the authorities. This study was undertaken to evaluate 400 consecutive patients receiving controlled substances in an interventional pain management practice in Western Kentucky to evaluate the prevalence of illicit drug use and opioid abuse and noncompliance with opioid therapy. Results indicated that patients covered by third-party insurance showed 17% (95% CI, 10%-24%) prevalence of illicit drug use, with patients on Medicare, with or without third-party insurance, showing 10% (95% CI, 4%-6%) prevalence, compared to patients on Medicare and Medicaid with 24% (95% CI, 16%-32%) prevalence, and patients with only Medicaid with 39% (95% CI, 29%-49%) prevalence of illicit drug use. In addition, combined use of illicit drugs and misuse of prescription drugs was also seen in a substantially greater proportion of patients in Groups III and IV, with the highest (60%) in Group IV with Medicaid only, followed by Group III with Medicaid supplementation of Medicare insurance in 40% of the patients. Overall illicit drug use, opioid abuse, and noncompliance of opioids is significant in patients in Western Kentucky receiving Medicaid as a primary insurance or as a supplemental insurance to Medicare, despite extensive monitoring, written agreement, and education.