Patient Test Information

Pharmacogenetic Tests 4

Common Questions

1. Should everyone have pharmacogenetic tests performed? Currently they are only indicated if a person is going to take, or is taking, a drug that has an accepted pharmacogenetic test associated with it.

2. Is pharmacogenetic testing required before taking certain drugs? No. The FDA may recommend this testing, as in the case of irinotecan, but it is not required.

3. Why am I only tested once? Your genetic make-up does not change over time. You may, however, have other pharmacogenetic tests performed if you take a different drug with a different associated pharmacogenetic test.

4. Does this mean my drug levels do not have to be monitored? No. Since there are other factors that affect drug levels besides your genetics, therapeutic drug monitoring may still be necessary.

5. What type of sample is used? A blood sample is obtained by inserting a needle into a vein in the arm. Saliva samples and buccal swabs, collected by brushing the inner side of the cheek with a swab, can also be used.

6. How do pharmacogenetic tests differ from genetic tests? Pharmacogenetic tests are performed to evaluate a person's potential response to a drug therapy. Most genetic tests have been developed to help diagnose or predict the development of a genetic disease, for forensic medicine purposes, and in establishing parentage. Another common use of genetic testing is to detect the genetic material (DNA or RNA) of bacteria and viruses to help diagnose an infection. (Read the article The Universe of Genetic Testing for more information.)

7. Will I be monitored differently after the test? You may be monitored differently depending on the results of the test, especially when starting the medication, changing the dose, or when adding or discontinuing another medication.

8. Should family members be tested? This is a question to discuss with your healthcare provider and your family members. In some cases it may be useful; in others it may only be relevant if they are going to be taking the same drug or a drug in the same class. Pharmacogenetic test results are useful information for a family member to share with the healthcare practitioner along with the family's medical history.

9. How do I know whether or not I should have testing done? You and your healthcare provider should consider the condition that you have, your history of drug-related side effects and/or adverse drug reactions, the drug therapies that are available, and the uses the test is intended for. Pharmacogenetic tests are not meant to stand alone but are meant to be used in conjunction with your other clinical findings.