What does pharmacogenetic testing tell you?
Pharmacogenetics allows patients and their providers to predict whether a medication may work well or whether it would be worth pursuing a different medicine. If you are about to begin therapy that requires medication, then knowing your personal pharmacogenetics helps reduce the number of medication choices. This knowledge can help reduce cost, time, and potential side effects; and at the same time increase the likelihood of treatment success.
Many patients may have tried multiple medications with little benefit or intolerable side effects. Pharmacogenetic testing can help find a medication that works better for you, stopping the cycle of trial and error.
Multiple medications may not work well in certain individuals. FDA prescribing information contains recommendations for dose adjustments or alternative medications for many medicines.
Examples
- Amphetamine and aripiprazole – CYP2D6 poor metabolizers may have higher concentrations with increased adverse effects. The FDA recommends starting at a lower dose or using an alternative.
- Codeine – CYP2D6 ultrarapid metabolizers may have much higher systemic concentrations of the active metabolite leading to increased adverse reaction risk and the potential of life-threatening respiratory depression or death, especially in children.
- Phenytoin – CYP2C9 intermediate or poor metabolizers may have higher concentrations with increased adverse reaction risk. Dosage adjustment or alternative therapy may be required for seizure control.
Knowing your pharmacogenetics profile ahead of time can greatly improve outcomes.
How is pharmacogenetic testing helpful to me?
With pharmacogenetic testing, you can better understand why some medications are preferable while others may be worth avoiding. Sharing your results with your physician will help them know which medicines have the greater potential to help in the future. If you experience a need for a medicine in the future, pharmacogenetic testing can help your physician choose a more appropriate line of therapy with less trial and error, fewer side effects, and improved outcomes.
- Pharmacogenetic testing can help you and your physician improve symptom control. Testing can help eliminate the need for multiple attempts or dose adjustments by starting with a medicine that will be more likely to be effective.
- Pharmacogenetic testing reduces the potential of severe adverse effects. All medications may lead to side effects. Side effects can be reduced by choosing medications that are more suitable based on your pharmacogenetic profile.
- Pharmacogenetic testing saves money. When you are treated with the best medication, the first time, with the right dosage; you will have fewer doctor’s appointments, fewer medical bills, fewer hospitalizations, and fewer prescriptions to fill.
Treating with the most appropriate medication based on the patient’s pharmacogenetic profile can reduce medication errors and hospitalizations while improving treatment outcomes. Pharmacogenetic testing improves overall healthcare.
How do I interpret pharmacogenetic test results?
When looking at a pharmacogenetics test report you will notice there are red, yellow, and green medications.
- Red medications – Avoid if able, may cause more side effects and be less effective.
- Yellow medications – Use with caution, may have increased side effects or decreased benefit, dose adjustments are common. An alternative may be preferred.
- Green medications – These medications are not impacted by the genes assessed. Use normal precautions but do not assume they are ‘safe.’
When looking at the pharmacogenetics results the genes evaluated are categorized into how they affect metabolism.
- Ultrarapid metabolizer – Highly increased activity
- Rapid metabolizer – Increased activity
- Normal metabolizer – Fully functional activity
- Intermediate metabolizer – decreased activity
- Poor metabolizer – Little or no activity
The type of metabolizer indicates how a gene product functions, not whether the medicine connected to it will work. The gene product then will affect the medication. Medicines are changed by your body through various processes. Sometimes this change activates the medication, and other times it inactivates the medication.
Examples
- Clopidogrel, or Plavix, requires activation by the body. If CYP2C19, a gene, is found to be an intermediate or poor metabolizer, then clopidogrel is not recommended because it will be ineffective.
- Meclizine, also known as Antivert, may need dosage adjustments in patients based on their CYP2D6 activity. One patient may find a small dose is effective, and another may find that they need a larger dose for any effect.
What makes pharmacogenetics testing so clinically relevant?
Pharmacogenetics, the science of how our bodies process medications, is continuing to grow. The more we learn, the more we realize that multiple medications are processed differently in different individuals. Knowing ahead of time how our body will react to a medication can help prescribers choose medicines based on the individual.
All new drugs in development are required to run pharmacogenetic testing. Part of this requirement is to distinguish if efficacy and/or side effects is a factor of the individual’s pharmacogenetics. This testing helps determine any issues that may arise besides regular population profiling based on ethnicity, gender, or age. Pharmacogenetic testing specifically focuses on aiding in the selection of therapeutics.
Pharmacogenetic information on multiple medications is already known and available. Including this knowledge when prescribing therapies can greatly improve patient outcomes. Hippocrates’ Oath states, “I will offer those who suffer all my attention, my science, and my love.” This science, then, should be applied as often as possible. Pharmacogenetic testing is now available in an affordable, easy-to-do, and easy-to-comprehend test.
Why is pharmacogenetics important?
Personalized medicine customizes treatment based on the individual. Treatment is based on each person’s uniqueness including ethnicity, gender, genes, environment, diet, lifestyle, and more. Looking at an individual’s pharmacogenetic profile is a part of personalized medicine.
Pharmacogenetics improves outcomes by predicting the drug response when incorporated into the medical decision-making process. Patients experience better symptom control, reduced side effects, greater adherence, and reduced time to optimal therapy.
Cost is a major factor for patients. Medication prices are rising, insurance prices are rising, and the economy is not keeping up. Patients are starting to have to decide whether to take their medication or pay their bills or eat.
Pharmacogenetics testing is an investment that ultimately reduces costs. Insurance costs are reduced because of the reduction of medication errors, reduction of hospitalizations, and improved patient outcomes. Patient costs are reduced because of the reduction of trial and error, reduced need for multiple medicines, multiple doctor visits, and multiple tests. Reduced costs are also due to the increased adherence to medications since there are reduced side effects. Patients and companies also save money by reducing the number of days missed from work.
Pharmacogenetic testing can improve trust between patients and providers. When a patient understands their provider is truly picking the best medication, the patient will be more likely to adhere to the medication and to listen to the advice of the prescriber. This then again leads to better patient outcomes as well as improved patient/provider relationships.
ClarityX offers pharmacogenetic testing. The ClarityX test provides information on more than 265 FDA-approved medications, an analysis of your current regimen and more.
https://www.fda.gov/medical-devices/precision-medicine/table-pharmacogenetic-associations
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5253119/
https://www.pharmgkb.org/chemical/PA450338/labelAnnotation
https://www.bu.edu/arion/files/2010/03/Arenas_05Feb2010_Layout-3.pdf
https://www.personalizedmedicinecoalition.org/Userfiles/PMC-Corporate/file/pmc_age_of_pmc_factsheet.pdf
