Medication Adverse Event Alert

November 30, 2006

MEDICATION: Methadone HCl

Dosage Forms:	oral tablets, oral and injection solutions
Manufacturers:	multiple (e.g., Roxane, Mallinckrodt, Vista Pharm, etc…)
Strengths:	tablets 5mg, 10mg, 40mg; oral solution 5mg/5ml, 10mg/ml; injection 10mg/ml

The following FDA Public Health Advisory was released on November 27, 2006:

Methadone Use for Pain Control May Result in Death and Life-Threatening Changes in Breathing and Heart Beat

"FDA notified healthcare professionals of reports of death and life-threatening adverse events such as respiratory depression and cardiac arrhythmias in patients receiving methadone. These adverse events are the possible result of unintentional methadone overdoses, drug interactions, and methadone's cardiac toxicities (QT prolongation and Torsades de Pointes). The reports underscore the importance of knowing methadone's toxicities and unique pharmacologic properties, including dosing and monitoring recommendations.

These deaths and life-threatening side effects have occurred in patients newly starting methadone for pain control and in patients who have switched to methadone after being treated for pain with other strong narcotic pain relievers. Methadone can cause slow or shallow breathing and dangerous changes in heart beat that may not be felt by the patient."

Recommendations: The FDA's alert offers the following considerations for dosing and monitoring

"Prescribing methadone is complex. Methadone should only be prescribed for patients with moderate to severe pain when their pain is not improved with other non-narcotic pain relievers. Pain relief from a dose of methadone lasts about 4 to 8 hours. However methadone stays in the body much longer-from 8 to 59 hours after it is taken. As a result, patients may feel the need for more pain relief before methadone is gone from the body. Methadone may build up in the body to a toxic level if it is taken too often, if the amount taken is too high, or if it is taken with certain other medicines or supplements.

• Patients should take methadone exactly as prescribed. Taking more methadone than prescribed can cause breathing to slow or stop and can cause death. A patient who does not experience good pain relief with the prescribed dose of methadone, should talk to his or her doctor.

• Patients taking methadone should not start or stop taking other medicines or dietary supplements without talking to their health care provider. Taking other medicines or dietary supplements may cause less pain relief. They may also cause a toxic buildup of methadone in the body leading to dangerous changes in breathing or heart beat that may cause death.

• Health care professionals and patients should be aware of the signs of methadone overdose. Signs of methadone overdose include trouble breathing or shallow breathing; extreme tiredness or sleepiness; blurred vision; inability to think, talk or walk normally; and feeling faint, dizzy or confused. If these signs occur, patients should get medical attention right away.