New advances will help patients respond better to medicines
Next time you find yourself in a crowd, take a look around. Notice that people come in all sizes, shapes and colors. These differences can be determined by genetic differences in all of us, and are cemented in our DNA and genes.
Genes can determine everything from eye and skin color to height. These same genes can also affect how we react to many medications. Doctors have long known that some medicines work great for some people and not so great for others.
In some circumstances, patients develop a serious side effect or complication from a medication, whereas many people who take the same medicine do not have the same bad experience and do very well. In fact, almost one million people per year in the U.S. experience adverse medication reactions, and it is estimated that close to 100,000 people die from adverse medication reactions. This is alarming.
To be fair, a person’s response to a particular medicine is also based on multiple factors including age, weight, gender, sex, health status, other current medications being taken, tobacco use, alcohol consumption, and environmental exposures. However, the major influence on how anyone responds to medications lives deep in their genes.
For example, if you have enzymes that break a medicine down quickly, there may not be enough of the medicine available to provide adequate help. In these cases, the medicine may be downright useless, or the patient may require larger doses for good effect.
Alternatively, if your genes produce enzymes that break medicines down slowly, too much may accumulate and cause unwanted or even toxic results. Also, these variations can have devastating results on babies who are being nursed by their mothers taking certain medications.
In fact, 10 percent of people receiving traditional pain medications don’t get any appreciable relief. This 10 percent figure holds true for most all medicines. Of the approximate 1,200 FDA-approved medications, approximately 125 (about 10 percent) will have widely varying effects based, in part, on a person’s individual genetics.
These medications are broad-spectrum and are used, in part, to treat the following conditions:
- Heart disease
- Bleeding disorders
- Addiction disorders
The good news is that doctors and researchers have gained a great deal of information and insight on how a person’s genetic makeup can affect the way they respond to specific medications. This field of research (examining how drugs are affected by a person’s genes) is called pharmacogenetics.
Now, with a simple test (either a swab of the inside of the cheek or a blood sample), doctors can look at key genes that code the enzymes that process and affect different medications in the body. This will allow physicians to determine how patients will respond to over 240 different medicines, and the number is growing monthly.
By selecting the correct medicines based on the test, your doctor will then have the ability to limit many adverse drug reactions, avoid medicines that don’t work for you, and avoid any unintentional interactions between the many drugs you may be taking or drugs you may take in the future.
The bad news is that the tests are new and not generally covered by insurance, but that should change over time. Paying out of pocket, the test will cost around $250-$300. That price, too, may come down over time. Two leading companies that perform the tests are OneOme and MilleniumHealth.
Clearly, doctors recognize that when it comes to medicines for their patients, one size does not fit all. The field of recommending the best medication for a patient based on their personal genetics is part of what doctors are calling “precision medicine” and will have a significant impact on the future practice of medicine.
If you are taking multiple medications, have a history of adverse medication reactions, have taken medicines that have not worked, have a complex health history, are being treated with medications from the list of medical conditions listed above, or just want good health information and peace of mind, be sure to have a discussion with your physician about taking a precision pharmacogenetic test.
Charles E. Crutchfield III, MD is a board certified dermatologist and Clinical Professor of Dermatology at the University of Minnesota Medical School. He also has a private practice in Eagan, MN. He received his M.D. and Master’s Degree in Molecular Biology and Genomics from the Mayo Clinic. He has been selected as one of the top 10 dermatologists in the United States by Black Enterprise magazine. Dr. Crutchfield was recognized by Minnesota Medicine as one of the 100 Most Influential Healthcare Leaders in Minnesota. He is the team dermatologist for the Minnesota Twins, Vikings, Timberwolves, Wild and Lynx. Dr. Crutchfield is an active member of both the American and National Medical Associations.