What is pharmacogenetics?
Pharmacogenetics is the study of how your genes influence your response to medications. Your genes determine two things: (a) what your body does to a medication and (b) what a medication does to your body.
What your body does to a medication.
Some of our genes encode enzymes--cellular machines--that break medications down into pieces in a process known as drug metabolism. These pieces are typically useless and pass out of your body naturally over time. This is why, for instance, you take ibuprofen every 8 hours, because that's the amount of time it takes the average person to work through most of the dose. Some medications, known as prodrugs, have to be broken into pieces before they become effective. An example is codeine which, on its own, has a little effect as a pain reliever, but is broken into hydromorphone and the more familiar morphine, which are much stronger pain relievers.
So what happens if your genes are a little different? Small changes in your genes can make a big difference in how your enzyme machines function. Some changes lead to faster metabolism, others slow it down, and still others can stop it altogether. Now imagine that dose of ibuprofen. Someone who can't break the drug down may get pain relief for a longer time or may experience side effects after repeated doses, as the drug builds up in the body. Someone who can't break down hydrocodone will be less likely to get the pain relief they need and will also experience side effects after repeated or increased dosing.
Sometimes our genes carry changes that make our metabolism of drugs faster. In this case, a person may need a higher dosage of a particular drug, including many antidepressants and blood pressure medications, to obtain the desired effect.
What a medication does to your body.
Pharmacogenetics can sometimes provide insight into whether or not a medication, once it gets where it needs to go, will have any effect at all. Let's say a dose of hydrocodone has been broken down into its component parts and now the morphine is knocking on the brain's door, looking to speak with a particular receptor. If that receptor is broken, the drug can knock all day long and will have little to no effect.
Now, pharmacogenomics cannot yet answer all our questions about why we respond to certain drugs and not others, or why some of us experience rotten side effects with medications that others can take with ease. Your pharmacogenetic profile can provide insights into the likelihood of your response to medications, though, and this is valuable when you and your doctor and pharmacist are trying to choose the right medication and the right dose for you.
Pharmacogenetics is the study of how your genes influence your response to medications. Your genes determine two things: (a) what your body does to a medication and (b) what a medication does to your body.
What your body does to a medication.
Some of our genes encode enzymes--cellular machines--that break medications down into pieces in a process known as drug metabolism. These pieces are typically useless and pass out of your body naturally over time. This is why, for instance, you take ibuprofen every 8 hours, because that's the amount of time it takes the average person to work through most of the dose. Some medications, known as prodrugs, have to be broken into pieces before they become effective. An example is codeine which, on its own, has a little effect as a pain reliever, but is broken into hydromorphone and the more familiar morphine, which are much stronger pain relievers.
So what happens if your genes are a little different? Small changes in your genes can make a big difference in how your enzyme machines function. Some changes lead to faster metabolism, others slow it down, and still others can stop it altogether. Now imagine that dose of ibuprofen. Someone who can't break the drug down may get pain relief for a longer time or may experience side effects after repeated doses, as the drug builds up in the body. Someone who can't break down hydrocodone will be less likely to get the pain relief they need and will also experience side effects after repeated or increased dosing.
Sometimes our genes carry changes that make our metabolism of drugs faster. In this case, a person may need a higher dosage of a particular drug, including many antidepressants and blood pressure medications, to obtain the desired effect.
What a medication does to your body.
Pharmacogenetics can sometimes provide insight into whether or not a medication, once it gets where it needs to go, will have any effect at all. Let's say a dose of hydrocodone has been broken down into its component parts and now the morphine is knocking on the brain's door, looking to speak with a particular receptor. If that receptor is broken, the drug can knock all day long and will have little to no effect.
Now, pharmacogenomics cannot yet answer all our questions about why we respond to certain drugs and not others, or why some of us experience rotten side effects with medications that others can take with ease. Your pharmacogenetic profile can provide insights into the likelihood of your response to medications, though, and this is valuable when you and your doctor and pharmacist are trying to choose the right medication and the right dose for you.
Phoenix Laboratory Consulting is owned and managed by Bronwyn Ramey-Hartung, PhD, out of a private office near Louisville, KY. Bronwyn has 15 years of experience in molecular genetics, with expertise in the design and validation of Laboratory-Developed Tests, high-complexity clinical laboratory operations, quality systems, regulatory compliance, and medical device software. Her pharmacogenetics specialties include CYP450 haplotype and copy number analysis, data interpretation, and reporting. LinkedIn Profile
