By Robert Preidt
HealthSCOUT Reporter

The old saying about how we're all the same on the inside doesn't apply when it comes to how our bodies deal with medications.

The difference is in our genes: While a drug may act a certain way in your body, the biochemical processes in someone else's body could cause it to behave quite differently.

The field of pharmacogenetics is trying to decipher that relationship between our genes and the effect medicine has on our bodies. It's research that could result in individualized drug therapy, which in turn could lead to more directed treatment with fewer drug-related complications and deaths.

For example, based on a simple blood test, a doctor could determine a patient's genetic profile and predict which drug, at what dose, would be most effective for that particular patient.

"Most clinicians . . . use a standard approach for dealing with the average patient who comes into their office. The problem is that we're not average. We have a lot of variability and that variability is reflected in our genetic makeup," says Peter Wedlund, associate professor at the College of Pharmacy, division of pharmaceutical sciences, at the University of Kentucky, Lexington.

One person will take an antihistamine and sleep for a long time, while another person can take the same medication and it will stop his runny nose without making him sleepy, he says.

Wedlund was one of the speakers talking about pharmacogenetics at the 52nd annual meeting of the American Association for Clinical Chemistry, held recently in San Francisco.

"The potential benefits (of pharmacogenetics) come in two areas. One is prescribing the right drug for the right patient at the right time. And the other is avoiding the wrong drug for the wrong patient at the right time," says Jerry Goldsmith, the association's vice president of marketing programs.

"It's going to be a revolution in the way drugs are prescribed and used," Goldsmith adds. "It really is getting into the area of medicine that is tailored for the individual."

Goldsmith notes that bad drug reactions are a huge part of the country's medical bill and pharmacogenetics could drastically alter that.

More than 7,000 Americans die each year because of drug errors, according to the National Academy of Science's Institute of Medicine.

Pharmacogenetics dates back about 50 years, but only recently has new technology brought it to the forefront. Molecular diagnostic techniques can give important clues as to how a drug is metabolized within the body and a patient's genetic information can be obtained much faster. This could make drugs more affordable.

"Those tools are working faster and faster and that's elevated pharmacogenetics to a higher level," Wedlund says.

Pharmacogenetics shows great promise in particular areas, including avoiding toxicity in the use of some anticancer drugs and better targeting of psychiatric medications.

But Wedlund cautions that it's still not clear how effective or useful pharmacogenetics will be in hospitals or clinics where patients might be receiving many kinds of medications and are subject to a variety of other factors.

"While the wish of those who work in pharmacogenetics is to get more effective, directed treatment for patients, the reality is one must be able to demonstrate it can be done practically," Wedlund says.

"These are not cheap tools to utilize," he adds. "So the question is, can you test for these deficiencies or variations in the population in an effective way without increasing health-care costs, but actually trying to diminish health-care costs?"

So while there's no question about the potential of pharmacogenetics, Wedlund says much more investigation is needed.

"It's clear that genetic variation does influence peoples' response and handling of drugs and can influence therapeutic outcomes. It's not as clear at this point how we're going to use that information to the biggest effect," he says.

What to Do: For more about pharmacogenetics, go to the American Association for Clinical Chemistry, or this announcement about a pharmacogenetics research network.