Summary of Opioids

Opioids are commonly prescribed because of their effective analgesic, or pain relieving, properties. Studies have shown that properly managed medical use of opioid analgesic compounds is safe and rarely causes addiction. Taken exactly as prescribed, opioids can be used to manage pain effectively.

Among the compounds that fall within this class—sometimes referred to as narcotics—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).

Opioids act by attaching to specific proteins called opioid receptors, which are found in the brain, spinal cord, and gastrointestinal tract. When these compounds attach to certain opioid receptors in the brain and spinal cord, they can effectively change the way a person experiences pain.

In addition, opioid medications can affect regions of the brain that mediate what we perceive as pleasure, resulting in the initial euphoria that many opioids 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.

Opioids may interact with other medications and are only safe to use with other medications under a physician's supervision. Typically, they should not be used with substances such as alcohol, antihistamines, barbiturates, or benzodiazepines. Since these substances slow breathing, their combined effects could lead to life-threatening respiratory depression.

Oxymorphone

Oxymorphone (Opana, Numorphan)  is a powerful semi-synthetic opioid analgesic that is derived from thebaine, and is approximately 6–8 times more potent than morphine. Clinically, it is administered as its hydrochloride salt via injection, or suppository; typically in dosages of 1 mg (injected) to 5 mg (suppository). Endo Pharmaceuticals markets oxymorphone in the United States as Opana and Opana ER. Opana is available as 5 mg and 10 mg tablets; Opana ER, an extended-release form of oxymorphone, is available as tablets in strengths of 5 mg, 10 mg, 20 mg, and 40 mg. As with other opioids, oxymorphone can cause physical dependency, and has the potential for abuse.

Oxymorphone is indicated for the relief of moderate to severe pain and also as a preoperative medication to alleviate apprehension, maintain anesthesia, and as an obstetric analgesic. Additionally, it can be used for the alleviation of pain in patients with dyspnea associated with acute left ventricular failure and pulmonary edema.

Opana® extended-release tablets are indicated for the management of chronic pain of all or most aetiologies and are indicated only for patients already on a regular schedule of strong opioids for a prolonged period. The immediate-release Opana® tablets are recommended for management of breakthrough pain for patients on the extended-release version.

Brand names

• Numorphan (suppository and injectable solution)

• Opana (tablet)

• Opana ER (extended-release tablet)