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Methadone for Pain

Worst Pills, Best Pills Newsletter article May, 2007

In the February 2007 Worst Pills, Best Pills News we wrote about the Food and Drug Administration’s (FDA) November 26, 2006 Public Health Advisory concerning the use of narcotic methadone for the treatment of pain. The FDA warned about the drug’s potential to cause life-threatening breathing problems and heart rhythm disturbances. Methadone, a narcotic, is also approved by the FDA to detoxify patients addicted to narcotics because it partially blocks the effects of narcotics. When it made...

In the February 2007 Worst Pills, Best Pills News we wrote about the Food and Drug Administration’s (FDA) November 26, 2006 Public Health Advisory concerning the use of narcotic methadone for the treatment of pain. The FDA warned about the drug’s potential to cause life-threatening breathing problems and heart rhythm disturbances. Methadone, a narcotic, is also approved by the FDA to detoxify patients addicted to narcotics because it partially blocks the effects of narcotics. When it made this safety announcement, however, the FDA negligently failed to point out that they had recommended a drastic reduction in the starting dose for pain to prevent some of these life-threatening adverse reactions.

The previous recommended starting dose for the drug for pain was 2.5 milligrams to 10 milligrams every three to four hours as necessary for a maximum of 80 milligrams per day. The new recommended starting dose of methadone for pain is now 2.5 milligrams to 10 milligrams every 8 to 12 hours – a maximum of 30 milligrams of methadone per day. This is more than a 2.5 fold reduction in the dosage for the initial treatment of pain.

This new recommendation is more in line with the lower recommended starting dose of methadone when it is used for narcotic detoxification. That recommendation usually does not exceed 40 milligrams per day for a period of two to three days.

Public Citizen Warning on New Methadone Dose

The FDA recommended dosages for patients starting methadone treatment for pain have been radically reduced.

The new approved starting dose is 2.5 milligrams to 10 milligrams every 8 to 12 hours – up to 30 milligrams per day.

The dangerous old starting dose for methadone was 2.5 milligrams to 10 milligrams every 3 to 4 hours as necessary – up to 80 milligrams per day.

No patient should ever receive more than 30 milligrams on day one for pain management, and thereafter dosage increases should be no more than 10 milligrams twice per week. Exceeding these limits can lead to death. 

The adverse effects seen with methadone when used for pain relief begin with the fact that the drug is very complex to prescribe. The following factors must be considered when the drug is prescribed for pain:

  • The full pain relieving effect of methadone is not seen until three to five days after treatment is begun.
  • The time it takes for one-half of a methadone dose to be eliminated from the body ranges from eight to 59 hours. This time is called methadone’s elimination half-life.
  • The pain relieving effect of methadone lasts from four to eight hours.
  • Methadone’s property of causing breathing problems peaks later and persists longer than its pain relieving effect.

Not only is beginning patients on methadone for the first time difficult, converting them from other narcotic pain relievers is also complicated. Further, it does not eliminate the possibility of methadone overdose, even in those patients that have been taking other narcotic painkillers.

Methadone does not act rapidly to treat acute pain and the toxic effects of the drug last longer than the drug’s ability to relieve pain. If pain is not adequately relieved, patients may be tempted, and prescribers may advise, to take an extra dose of the drug. This is the normal way that patients and prescribers think about managing episodic acute pain. However, because of the complexities of methadone dosing, this may lead to accumulation of the drug in the body and an inadvertent methadone overdose.

Methadone remains a useful treatment for patients undergoing narcotic detoxification. However, the FDA’s black box warning for the drug, reproduced in full with this article, says in effect that that methadone is a last choice drug and questions whether or not it should be used either for acute or chronic pain at all.

FDA BLACK BOX WARNING FOR METHADONE

Deaths, cardiac and respiratory, have been reported during initiation and conversion of pain patients to methadone treatment from treatment with other opioid agonists [narcotic painkillers]. It is critical to understand the pharmacokinetics [absorption, distribution, metabolism, and excretion of drugs] of methadone when converting patients from other opioids. Particular vigilance is necessary during treatment initiation, during conversion from one opioid to another, and during dose titration [adjustment].

Respiratory depression is the chief hazard associated with methadone hydrochloride administration. Methadone’s peak respiratory depressant effects typically occur later, and persist longer than its peak analgesic effects, particularly in the early dosing period. These characteristics can contribute to cases of iatrogenic [physician induced] overdose, particularly during treatment initiation and dose titration.

In addition, cases of QT interval prolongation and serious arrhythmia (torsades de pointes) have been observed during treatment with methadone. Most cases involve patients being treated for pain with large, multiple daily doses of methadone, although cases have been reported in patients receiving doses commonly used for maintenance treatment of opioid addiction.

Methadone treatment for analgesic therapy in patients with acute or chronic pain should only be initiated if the potential analgesic or palliative care benefit of treatment with methadone is considered and outweighs the risks.

The FDA’s scandalous inaction on methadone

Clearly, it was irresponsible of the FDA not to highlight the major change in the recommended starting dose of the drug for the treatment of pain when it made its announcement in November, 2006. Worse yet, it is scandalous that the dose of methadone recommended by the FDA has been known to be dangerous for at least a dozen years. In 1995, the Institute of Medicine reviewed methadone regulations, policies and practices. The authors of the review concluded:

In light of the above [evidence], the committee recommends that the regulations retain the language that "the amount of the initial dose should not exceed 30 mg" in order to protect the safety of the newly admitted methadone [maintenance] patient.

A physician colleague wrote FDA commissioner Andrew von Eschenbach on December 21, 2006, to warn the agency of the danger of not effectively warning patients, physicians, and pharmacists of the major change in the dosage recommendation. He stated:

There is no reason to believe that physicians who have been prescribing methadone, pharmacists that have been dispensing it or patients that have been receiving it will be aware of the marked change in recommended dosage. There is an urgent need to communicate this information at once to every practitioner and pharmacist in the country. In addition, I urge that FDA require, effective immediately, that every package of methadone that is dispensed for pain management carry a warning that can be neither overlooked nor misinterpreted, stating that doses exceeding 30 mg in any 24-hour period can cause death and must be avoided without the express direction of the prescribing physician. It is not hyperbole to say that every day of delay jeopardizes the lives of patients.

We completely agree.

What You Can Do

You should not use methadone for acute or chronic pain unless, on the rare chance, there is no other pain medication that adequately controls your pain.

Alternatives include NSAIDs (non-steroidal anti-inflammatory drugs) and narcotics such as codeine or, possibly, morphine.

You should seek medical help immediately if you are taking methadone and experience symptoms that suggest a heart rhythm disturbance such as palpitations, dizziness, lightheadedness or fainting.

You should seek medical help immediately if you have a friend or family member taking methadone who shows symptoms that suggest an overdose such as slow or shallow breathing; extreme tiredness or sleepiness; blurred vision; inability to think, talk or walk normally; and feeling faint, dizzy or confused.