| TARPON SPRINGS, FL -- September 5, 2007 -- The National Center for Health Statistics reports 3,849 poisoning deaths, involving methadone, in 2,004. Eliminating S-Methadone, from the mixture of R and S methadone, used in the United States, could reduce deadly cardiac arrhythmias and decrease the dangerous, unpredictable variations, in methadone therapeutic dose, between individuals. The therapeutic methadone dose is dangerously close to the fatal dose, partially due to the huge methadone half life variation, between patients. Replacing the racemic methadone mixture, used in United States, with pure R methadone, used in Germany, could reduce the United States methadone death epidemic," explains Rick Sponaugle, MD, Medical Director of Florida Detox.
Racemic methadone prescribed in the United States , is a 50 percent mixture of the active R methadone.with 50 percent S methadone, which are mirror images, of each other. R methadone is 50 times more active for pain control and binds 10 times more strongly to opiate receptors, than S methadone. According to a Swiss study of 179 patients, S-methadone causes cardiac arrhythmias or an irregular heartbeat, but provides little pain relief or opiate craving decrease. Swiss researchers determined S methadone was 3.5 times more likely to cause prolonged QT interval arrhythmias, than R methadone. Approximately 6 percent of patients metabolize or detoxify S methadone more slowly, due to decreased levels of the CYP2B6 enzyme. The Lausanne researchers determined these individuals were 4.5 times more likely to suffer dangerous prolonged QT interval arrythymias.
Inactive S methadone contaminates racemic R/S methadone mixtures, and increases the methadone dose needed to provide pain relief or prevent opiate craving. A Swiss study of 180 methadone maintainence patients, in 2000, found R methadone serum levels of 250 ng/ml prevented unprescribed opiate use as effectively as serum levels of 400 ng/ml of racemic R/S methadone. The same study found racemic R/S methadone doses varying from 55 mg/ day to 921 mg/day were required to produce a 250 ng/ml R methadone serum level, in a 70 kg patient. These huge variations in individual patient response to methadone dose demonstrate the unpredictability of the safe, effective methadone dose for a particular patient.
For many methadone patients, the fatal and therapeutic methadone doses are almost the same. Methadone patients are 7 times more likely to die from a methadone overdose, during the first two weeks of methadone treatment, while their individual response to methadone is determined. Eliminating cardiotoxic S methadone, from R methadone would decrease the methadone dose needed to control pain and opiate craving and reduce the total methadone dose required.
"The cost factor is not very important. Methadone is a very cheap drug. It only costs around SFr0.80 [$0.65] a day per patient and would rise to around SFr2.5 if we just use R-methadone," explained Hugues Abriel, MD, PhD, Department of Pharmacology and Toxicology, University of Lausanne, Switzerland. Most methadone clinics could easily absorb the increased cost of pure R methadone, since they report profits, from 16 to 50 percent of revenue, after taxes. CRC, treating over 20,000 United States methadone patients daily, reports daily profits per Methadone patient of $10.91 to $11.07.
"Since replacing R/S methadone with safer R methadone would reduce methadone cardiotoxicity and dangerous methadone half life variations, the FDA should expedite any approvals required for R methadone to be prescribed, in the United States. United States methadone patients deserve treatment with the safer R methadone, used in Germany. Physicians should also be required to obtain additional training and certification, before they are allowed to prescribe methadone, which is killing more Americans, than heroin," said Dr. Sponaugle, who is Board Certified in Addiction Medicine and Anesthesiology. |
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