The U.S. Food and Drug Administration announced Wednesday that it was investigating the safety of codeine for post-operative pain relief in children following reports of three deaths and one life-threatening emergency related to its use after tonsil surgery.
The children were between the ages of 2 and 5. All had received standard doses of codeine, but doctors believe each had a genetic trait that caused them to develop toxic levels of drug in their bodies.
â€œThis will be news to the majority of [doctors] who are not well versed in opioid pharmacology, and it is very important,â€ says Dr. Elliot Krane, a professor of anesthesia and pediatrics at Lucile Packard Childrenâ€™s Hospital.
The reason that codeine may be a special case is that it requires extra processing by the liver to work.
â€œCodeine doesnâ€™t work in its natural form,â€ explained Dr. Joseph R. Tobin, professor and chairman of anesthesiology at Wake Forest University School of Medicine. â€It must be converted by enzymes in the body to its active form.â€
This active form is morphine. For most patients, taking codeine leads to a relatively safe and therapeutic level of morphine in the body. In nearly a third of the patients who metabolize the codeine slowly, there may be minimal or no effect.
However, in the rare case of â€œultra-rapid metabolizers,â€ the liver quickly converts the codeine into high levels of morphine in the blood â€” a potentially deadly situation.
â€œIf you are an ultra-rapid metabolizer, then the concentration of the active form of the drug can rise in the patientâ€™s bloodstream quickly,â€ said Tobin. â€œWhen this is also associated with residual anesthetics, a child may be at risk to stop breathing or become completely obstructed.â€
Unfortunately, few people are likely to know whether they are slow, regular, rapid or ultra-rapid metabolizers until they take codeine for the first time. Also, because the mechanism controlling this drugâ€™s metabolism is based on a personâ€™s liver enzyme properties, there is no way to change how the drug is processed in any one person.
The genetic test costs a few hundred dollars, but it might save you money and save your life later according to this.
Experts report that approximately $300 billion is wasted each year on drugs which apparently do not work in people who have certain genes. These people never receive the full benefit from these drugs.Â Others are getting dangerous side effects.Â … Based on what type of genes you carry, you may be:
- a poor drug metabolizer
If you are a â€œpoor metabolizerâ€, you do not break down drugs well.Â This may result in too much drug in the body which may lead to a dangerous side effect or even death.Â In some cases, your body may not be able to break down certain drugs to their working form and therefore the drugs will not work properly.
- an extensive or â€œnormalâ€ drug metbolizer
You metabolize drugs at the normal rate.
- an ultra-rapid drug metabolizer
If you are an â€œultra-rapidâ€ metabolizer, this means you break down drugs too fast, causing them to be of no use in the body.Â If medications do not work properly, conditions such as high blood pressure, blood disorders, and cancer will be left untreated and may even lead to death.
… Genetic tests for drug response usually cost a few hundred dollars.Â The cost of having a genetic test done should be weighed against the cost-savings and benefits that might result.Â If you know the results of your genetic test before you start taking a medicine, your doctor will know which drug is best for you.Â You will not waste money purchasing medicines that the test shows will not work or cause dangerous side effects.Â This could be life-saving in many diseases. Â Â If you weigh the cost of the test against the costs you would face if you developed a serious side effect or took a drug that did not work, the cost of taking a test would be far less than the cost of treating complications.
Getting tested is a once in-a-lifetime experience because your genes do not change over time.Â Since many drugs are metabolized by one enzyme, you may only need one test.Â Once you are tested, you can keep your genetic test results for the rest of your life and share them with future care professionals.
Some insurance companies may cover genetic testing depending on your policy and your reasons for testing.Â If you are interested in getting tested, you can call your insurance company to find out the cost and requirements for testing.Â Your doctor will have to order the test for you. …