DNA Testing Can Guide Medication Decisions

By Ted Swing, Ph.D.

The selection of appropriate medications and doses is an important part of pain management. In some cases, the wrong medication or dose can lead to less pain relief than would be expected. In other cases, a particular medication can cause undesirable side effects or serious health risks. These challenges are sometimes caused by individual differences in how patients respond to certain medications.

Some patients are hypermetabolizers of certain pain medications. This means that their body breaks that medication down more quickly than most people. As a result, less of the medication reaches the brain and the patient gets less pain relief than would be expected for the dose they are taking. Hypermetabolizers of a pain medication may end up being prescribed high doses of a medication and may not end up getting adequate pain relief from that medication.

In other cases, patients are hypometabolizers of a pain medication, meaning their body breaks that medication down too slowly. Consequently, even typical doses of that medication may stay in their body for a longer period of time. For a daily pain medication, this can lead to strong, unpleasant side effects. Long-term use of a poorly metabolized medication can be harmful, potentially leading to hospitalization.

The problems of hypermetabolism and hypometabolism can be difficult for both patients and physicians to detect. However, a patients’ hypermetabolism and hypometabolism are often limited to only certain specific medications. In some cases, once identified, the problem might be addressed by the patient changing to another medication that their body metabolizes properly. In other cases, the patient may respond best simply ceasing a problematic medication.

Pain management physicians have begun to utilize DNA testing to identify individual differences in medication metabolism. These individual differences in how each person’s body breaks down a medication are linked to a number of specific genes. A simple cheek swab can be used to test a patient’s DNA to reveal whether they are a hypermetabolizer or hypometabolizer for a wide variety of pain medications. This can be used to guide subsequent medication treatment.

At Arizona Pain, we are starting a program to evaluate DNA testing for selected patients to determine if this can help identify appropriate medications and avoid inappropriate medications for some individuals. Some patients may be suggested to receive this DNA testing. Because a person’s DNA does not change, this test only needs to be completed once in a patient’s life. This type of DNA testing typically costs several hundred dollars to complete, but some health care providers, such as Medicare, will cover the cost of this test. Others cover part of this cost.

Ted Swing has more than nine years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.