May cause CNS depression (caution in CNS depression or coma). Effects may be potentiated when used with other sedative drugs or ethanol. Use with caution in history of drug abuse or acute alcoholism (potential for drug dependency exists; tolerance, psychological and physical dependence may occur with prolonged use). Use with extreme caution with head injury, intracranial lesions, or elevated intracranial pressure (exaggerated elevation of intracranial pressure may occur). May cause hypotension (caution if hypovolemia, cardiovascular disease (including acute myocardial infarction), or drugs which may exaggerate hypotensive effects). Use with caution in hypersensitivity reactions to other phenanthrene-derivative opioid agonists (codeine, hydrocodone, hydromorphone, levorphanol, oxymorphone). May obscure diagnosis or clinical course of acute abdominal conditions. Use with caution in adrenal insufficiency, including Addison’s disease, and in biliary tract dysfunction; acute pancreatitis may cause constriction of sphincter of Oddi, in mild hepatic dysfunction (contraindicated in moderate-to-severe impairment). Use with caution in morbidly obese patients, in prostatic hyperplasia and/or urinary stricture, in renal impairment, and in pre-existing respiratory compromise (hypoxia and/or hypercapnia), chronic obstructive pulmonary disease or other obstructive pulmonary disease, and kyphoscoliosis or other skeletal disorder which may alter respiratory function (critical respiratory depression may occur). Use with caution in thyroid dysfunction, in debilitated patients (higher risk for critical respiratory depression), and in the elderly (may be more sensitive to adverse effects). Extended release oral formulation not suitable for use as «as needed» analgesic. Tablets should not be broken, chewed, dissolved, or crushed (should be swallowed whole). Extended release formulation intended for use in long-term, continuous management of moderate-to-severe chronic pain; not indicated for use in immediate postoperative period (12-24 hours). Coingestion of ethanol or ethanol-containing medications with extended release formulation may result in accelerated release of drug from dosage form, abruptly increasing plasma levels, which may have fatal consequences. Concurrent use of agonist/antagonist analgesics may precipitate withdrawal symptoms and/or reduced analgesic efficacy in patients following prolonged therapy with μ-opioid agonists. Abrupt discontinuation following prolonged use may also lead to withdrawal symptoms. Some quinolones may produce false-positive urine screening result for opiates using commercially-available immunoassay kits. May cause elevation in amylase (due to constriction of sphincter of Oddi).