I had something similar done several years ago. It was a blood only test, but it sounds like the same thing. They did genotyping of genes that encode for the 3 major cytochrome P450 pathways in the liver. CYP450 is a very important enzyme involved in many metabolic processes, including drug metabolism. There are MANY more than 3 CYP450 pathways, but these 3 pathways (CYP2D6, CYP2C9, and CYP2C19) are responsible for metabolizing the majority of drugs that are broken down in the liver -- including most anti-depressants and pain medications.
One of my docs had me tested after years of not responding to pretty much any medication. We were especially concerned about
my lack of response to essentially any and all all anti-depressants, but also my lack of response to pain medications (both opioid and non opioid meds).
It turns that I have some genetic mutations that makes 2 of these three pathways highly abnormal in me. One of them (which is considered "THE major pathway") is barely functional, if at all, and another one (which is considered "the second major pathway") does not work at all. Unfortunately, these 2 pathways together metabolize the vast majority of all pain medications, and antidepressants, as well as NSAIDs -- which explains my lack of response to everything. The head of the genetics lab actually called my doctor personally, because my results were so unusual.
The test was definitely helpful in explaining why I don't respond to anything, but unfortunately it didn't provide me with much in the way of medication options, as the list of (pertinent) medications metabolized by the one functioning pathway is very small. My doctors and I now have to look carefully at each and every medication that they want to put me on before it is prescribed, and there are many medications that I absolutely cannot take (including essentially all OTC pain relievers, with the exception of tylenol), as certain medications could cause liver damage, toxicity, or other serious side effects due to my body's inability to metabolize the medication. It also means having to adjust doses of medication that may only be partially metabolized & being careful to start new medications slowly, so we can pick up on any problems early on (I did have one serious reaction to one such medication a couple years ago).
My doctor also has to write a letter to the hospital & surgeon any time that I have surgery. As they need to know that they have to be careful with what & how much anesthesia they use, and also that I cannot metabolize certain pain medications, or that they need to use different dosages.
Anyways, I hope the testing provides you and your doc with some useful information that they can use to adjust your treatments, if necessary, & come up with the best treatment plan for you!
Oh, I'll also mention that there have been some studies done that correlate the presence of these genetic abnormalities with an increased risk/incidence of depression, which I find interesting, since depression has always been a big issue for me.
Post Edited (skeye) : 3/8/2013 9:54:51 PM (GMT-7)