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"The promise of pharmacogenomics, the study of the
role of inheritance in the individual variation in drug response,
lies in its potential to identify the right drug and dose
for each patient." New England Journal of Medicine,
Vol. 348, No. 6, February 6, 2003
 Pharmacogenomics is the science of customizing drug
therapy to individual patients based on their genetic makeup.
The way a person's body responds to drugs is an inherited
trait. This is why drug effectiveness is highly variable and
why some people suffer serious side effects--even death--from
recommended dosages.
Now by being able to "see" the genotype of an individual
patient, drug therapy can be customized for optimum effect.
Gene tests give doctors detailed information on an individual
inherited ability to metabolize specific drugs, specific recommendations
for which drugs to use, and which to avoid.
The result is more effective treatment, fewer adverse reactions
and side effects, and fewer fatalities.
Pharmacogenomics not only applies to the dosages for prescription
drugs, but also the effects of OTC drugs, herbals, lifestyle
drugs (nicotine, caffeine, cocaine, etc.), food, and environmentals.
Drug Variability
The fact that drug response is inherited is not new. Before
genomics, doctors studied familial patterns of drug response
to ascertain an individual's likely response. More than one
hundred medications were known to have inherited variability,
including codeine, antidepressants, antihypertensives, and
statins. This is why drugs for the treatment of Alzheimer's,
osteoporosis, incontinence, HIV, and cancer, for example,
have proven efficacy rates of less than 40%.
Drugs administered in "proper" doses can sometimes
cause serious adverse reactions, even death. There are over
2 million adverse drug reactions each year in the US serious
enough to cause hospitalization and over 100,000 deaths, making
adverse drug reactions the 4th leading cause of death.
Now gene tests provide specific, solid data that can be used
to prescribe optimum doses for individual patients based on
their ability to metabolize drugs. Pharmacogenomics minimizes
dosage trial and error. It is superior to the current system
of setting recommended doses based on statistical averages
from populations of test patients.
How Pharmacogenomics Works
Pharmacogenomics begins with a gene test-a swab or blood
sample sent to a lab. The test contains a full analysis of
a patient's ability to metabolize specific drugs. Because
the patient's genotype never changes, the data is kept in
a database and is valid for life.
On a cellular level, pharmacogenomics looks at the drug pathways-the
enzymes that metabolize drugs. The majority of commonly used
drugs are broken down by a few major metabolic pathways .
Variations in a person's genes determine the balance of enzymes
causing some drugs to be metabolized too quickly, others too
slowly. Some pathways are missing altogether.
If a particular drug is metabolized too quickly, the body
eliminates it before it can have a therapeutic effect. It
is ineffective. It should either be prescribed at a higher
dose, or a substitute drug found.
If a drug metabolizes too slowly, or not at all, elevated
levels of the drug will accumulate in the bloodstream, causing
toxic effects and adverse reactions. It should be prescribed
in lower doses, or not at all.
Benefits of Pharmacogenomics
Pharmacogenomics is available now to provide much more accurate,
personalized drug regimens and to reduce adverse side effects
or even death.
- It is a scientifically-based method for evaluating how
lifestyle, diet, OTC drugs, and recreational drugs affect
therapy.
- It reduces trial and error to find the best drug combinations
for treating a disease or condition.
- It gives physicians a way to build their practice, and
differentiate from other practices by offering advanced
genetic medicine.
- It minimizes the liability from trial-and-error approaches
to therapy.
- When pharmacogenomics becomes widespread, it will help
reduce overall health costs.
More Information
Links to additional information on pharmacogenomics, studies,
and case studies are available on the
Resources Page.
Pharmacogenomic testing and information packages can be obtained on the Products page.
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