Methadone a double-edged painkiller

Once used chiefly in addiction treatment centres as a replacement for heroin, Methadone, presently prescribed by family doctors in the US for throbbing backs, joint injuries and a host of other severe pains, has come under scrutiny.

The drug is a synthetic form of opium that is a long lasting and powerful pain reliever. Being cost effective, it has helped millions of people, but is also one of the fastest growing cause of narcotic deaths in the US.

That is because of its abuse by thrill seekers, and on account of errant prescriptions by doctors who are not adequately familiar of the associated risks.

According to reports, it has been the cause of almost twice as many deaths as heroin, and is in the league of the tolls taken by painkillers such as OxyContin and Vicodin.

Doctors caution that this drug is ''a wonderful medicine used appropriately'', but is an unforgiving foe if not used correctly, which calls for medical expertise when it is prescribed, since in a number of cases, methadone has caused the death of legitimate patients who followed the directions of the doctor.

Federal regulators are only now waking up to the dangers of widespread methadone prescriptions, blaming ''imperfect'' monitoring systems. For some time, a dangerously high dosage recommendation stayed on board the Food and Drug Administration (FDA) approved package insert right upto late 2006.

The FDA-approved package insert has recommended starting doses for pain at up to 80 mg per day, a level which they now realise could cause death in patients who have not recently used narcotics. The FDA has now adjusted the recommendation, and is looking at options that would require doctors to take special classes on prescribing narcotics.

Methadone prescriptions in the US also increased as a result of changing attitudes in the medical fraternity in the 1990s, with doctors accepting debilitating pain as an often undertreated condition. The medical insurance industry also took to the drug as a generic, cheaper alternative to other long-lasting painkillers such as OxyContin. Consequently, methadone prescriptions went up by 700 per cent between 1998 and 2006.

However, experts point out that a number of doctors still do not understand how slowly methadone is metabolised, and how greatly patients differ in their responses. That results in some doctors prescribing too much of the drug too fast that lets methadone build up to dangerous levels, while others some fail to warn patients about the drug's potential dangers of mixing with alcohol or other sedatives. Two other causes are doctors not staying in contact during the initial week of the prescription of the drug, and patients not following doctor's orders.
 
The US federal government has now started sponsoring voluntary classes to teach doctors about all the precautions needed with methadone, starting with a progressive prescription style that starts with low doses, and screening their patients for addictive behaviour.