The use of prescription narcotics for the treatment of pain can lead to addiction – compulsive, often uncontrollable drug use by an individual, despite the negative consequences. The American Academy of Pain Medicine, the American Pain Society and the American Society of Addiction Medicine jointly issued the following definition of addiction:

Addiction is a primary, chronic, neurobiologic disease, with genetic, psychosocial, and environmental factors influencing its development and manifestations. It is characterized by behaviors that include one or more of the following: impaired control over drug use, compulsive use, continued use despite harm, and craving.

A narcotic is an addictive drug, such as opium, that reduces pain, alters mood and behavior and usually induces sleep or stupor. Natural and synthetic narcotics are used in medicine to control pain.

Among the compounds that fall within this class—sometimes referred to as opioids —are morphine, codeine, and related medications. Morphine is often used before or after surgery to alleviate severe pain. Codeine is used for milder pain. Other examples of opioids that can be prescribed to alleviate pain include oxycodone (OxyContin—an oral, controlled release form of the drug); propoxyphene (Darvon); hydrocodone (Vicodin); hydromorphone (Dilaudid); and meperidine (Demerol), which is used less often because of its side effects. In addition to their effective pain relieving properties, some of these medications can be used to relieve severe diarrhea (Lomotil, for example, which is diphenoxylate) or severe coughs (codeine).

Narcotics can affect regions of the brain that mediate what we perceive as pleasure, resulting in the initial euphoria that many of these drugs produce. They can also produce drowsiness, cause constipation, and, depending upon the amount taken, depress breathing. Taking a large single dose could cause severe respiratory depression or death.

Long-term use of prescription narcotics can also can lead to physical dependence — the body adapts to the presence of the substance and withdrawal symptoms occur if use is reduced abruptly. This can also include tolerance, which means that higher doses of a medication must be taken to obtain the same initial effects.

Physical dependence is not the same as addiction. Physical dependence can occur even with appropriate long-term use of narcotics and other medications. People taking prescribed narcotic medications should not only be given these medications under appropriate medical supervision, but also should be medically supervised when stopping use in order to reduce or avoid withdrawal symptoms. Symptoms of withdrawal can include restlessness, muscle and bone pain, insomnia, diarrhea, vomiting, cold flashes with goose bumps ("cold turkey") and involuntary leg movements.

Addiction to prescription medications can be treated. Examples of available treatments include:

• Methadone, a synthetic opioid that blocks the effects of heroin and other narcotics, eliminates withdrawal symptoms and relieves craving. It has been used for over 30 years to successfully treat people addicted to narcotics.
• Buprenorphine, another synthetic opioid, is a recent addition to the arsenal of medications for treating addiction to heroin and other opiates.
• Naltrexone is a long-acting opioid blocker often used with highly motivated individuals in treatment programs promoting complete abstinence. Naltrexone also is used to prevent relapse.
• Naloxone counteracts the effects of narcotics and is used to treat overdoses.