A Comparison of the Addiction Liability of Hydrocodone and Sustained Release Morphine

A placebo-controlled, double-blind, crossover trial will be conducted providing study subjects either hydrocodone/acetaminophen 30mg/975mg, sustained release morphine 45mg or placebo on separate GCRC visits. A long acting comparator (slow-release morphine sulfate 45 mg) will be chosen because of its putative equianalgesic effects to the dose of hydrocodone (30 mg) selected. Subjects will participate in the three sessions at the UC Davis/Mather Medical Center General Clinical Research Center (GCRC) at intervals of 7-10 days. Sessions will be approximately 360 min in duration. Subjects will receive either hydrocodone/acetaminophen or sustained release morphine around-the-clock for 7-10 days prior to the experimental session. At each experimental session, an assessment of abuse liability will be completed before the intake of medications, as well as at 0, 60, 120, 180, 240 minutes after the ingestion of the study medication.

Inclusion criteria

• Patients with chronic pain for periods greater than 6 months
• Patients taking greater than 80 mg morphine equivalents of a short acting opioid (>8 vicodin or 4 oxycodone/day)
• Referral to Pain or Substance Abuse Clinic for self-escalation of opioids

Exclusion criteria

• Inability to understand and comprehend spoken English
• Patients with Munchausen's syndrome
• Patient has a history of Peripheral Vascular Disease
• Patient has a history of Raynaud's Phenomenon
• Liver Disease; Child's classification greater than 1 (liver cirrhosis) will be excluded
• Renal disease (BUN >25 or Cr >1.5)
• Congestive Heart Failure; Subjects with New York Heart Association (NYHA)Heart Failure Symptom Classification System Level of Impairment II, III and IV will be excluded
• Coronary artery disease; recent MI within the past six months or recent history of angina not controlled with NTG within the past six months
• Hypertension; 1)previously normotensive subject; systolic bp >140 mm Hg and diastolic bp > 90 mm Hg 2) Hx of active treatment with antihypertensive medications; systolic bp >150 mm Hg and diastolic bp > 100 mm Hg
• Cerebrovascular disease; recent history within the past year of a transient ischemic attack or recent history within the past year of a cerebrovascular event
• Malignancy requiring active treatment
• Patient is pregnant (as ascertained by a self-report and a mandatory commercial pregnancy test before any study medication is consumed)