A Mother’s Story: Avoiding My Baby’s Potential Overdose


“…the possibility he could have suffered a horrible consequence is very real.” –Sarah Zeller

Full disclosure: I am currently employed by Genelex Corporation and have been since 2011. However, I am writing this piece first and foremost as a patient and as a mother.

In 2012, I was pregnant with my first child. I had not completed the pharmacogenetic testing that is provided to all Genelex employees, much to the surprise of my co-workers. I remember thinking at the time: “Hey, I don’t really take medications. Sometimes a little over the counter stuff for pain, but I’m not really ON anything.” In fact, if I can help it, I try to avoid taking both over-the-counter medications and prescriptions. I was also planning on having a drug-free labor and birth. So really, how was this test going to apply to me? But since the testing was free, I figured it was worth it to just get it done to get my manager off my case.

My results revealed that I am a CYP2C9 Intermediate Metabolizer and a CYP2D6 Ultra Rapid Metabolizer. For those of you who have no idea what this means, let me elaborate a bit. Both of these pathways are responsible for processing a fairly robust number of common medications. For example, most NSAIDS (ibuprofen, etc.) are processed through the CYP2C9 pathway and many opioids (codeine, tramadol, hydrocodone, etc.) are metabolized through the CYP2D6 pathway. Let me give you a few practical examples. As an Intermediate Metabolizer of CYP2C9, I need to be careful about potential bleeding when taking NSAIDS, as I’m processing the drug more slowly than a normal metabolizer would. And as a CYP2D6 Ultra Rapid Metabolizer, codeine is being turned into morphine in my body at a much faster rate than a normal metabolizer, which can very quickly lead to toxicity and overdose.

Honestly, this information was surprising as I had assumed I was going to be “normal” across the board. However, a look at a past reaction to codeine made much more sense with these results in hand. Nearly twenty years ago, a prescribed dose of codeine made me violently ill. I chalked it up to having an allergy and for two decades I listed “codeine” in the allergy section of my health questionnaires. It seemed pretty cut and dry. I’ve been lucky since that first reaction because I haven’t needed to take heavy duty pain medication since then.

Let me focus on WHY my test result impacted me so much and the reason I want to share my story. I didn’t really think this information would apply to me for the reasons mentioned above. I was pretty confident that I would have a drug-free, natural delivery. But the birth of my first child didn’t go as planned, and I wound up having an emergency C-section.

I remember reading an article about a breastfeeding mother who accidentally overdosed her infant son while she was taking codeine. After his tragic death, a pharmacogenetic test determined she was a CYP2D6 Ultra Rapid Metabolizer. Essentially, she was converting codeine to morphine too quickly and her son died from morphine poisoning. Since this happened, warnings have been issued about the dangers of nursing while taking codeine-based medications due to the possibility of being a CYP2D6 Ultra-Rapid Metabolizer. Subsequently, there has been another warning about giving codeine to children after surgery for the removal of adenoids or tonsils due to similar dangers.

When thrust into an unplanned surgery, my pharmacogenetic test results armed me with information that kept me and my precious newborn safe. I was able to advocate for myself as a patient and tell the medical staff that I was not simply allergic to codeine – codeine was dangerous for me and could be deadly for my baby. There were alternatives to managing my pain that didn’t put us at risk. And let me tell you, my son nursed like a champ from day one: he never missed a meal. Had I been taking codeine for pain, the possibility he could have suffered a horrible consequence is very real.

My second child is due any day, and there is a chance that I will once again need pain medication. My delivery team is well aware of the best ways to manage my pain and what medications to administer that will not be harmful to me or my baby. I have tremendous peace of mind knowing this is one thing that I don’t have to worry about during the birthing process.

Over the years, I have been enmeshed in the fight to make pharmacogenetic testing standard of care and establish credibility within the medical community. Now, when someone asks me who should have this test, I firmly reply without hesitation, “Anyone who might need to take medication.” So, if you’re on the fence about getting this test done for yourself or prescribing it for a patient, think about the long-term benefits and consider the potential negative outcomes. Ask yourself, “What you would do if you were making a decision for your child?”

My personal experience made me a believer of this test. We tested our first born and will test our second child as well, because I believe this information could save them from adverse drug events over their lifetime. Their results can be used as preventative care down the road. It’s so simple and in my case, a no-brainer. The health of my kids is my absolute first priority.