Medication Safety: Multiple Breakdowns, Multiple Protections
November / December 2006
Medication Safety
Multiple Breakdowns, Multiple Protections
A 52-year-old heart transplant patient was admitted to the hospital with fever and fatigue. Upon further evaluation, he was found to have severe pancytopenia. The patient had been taking several immunosuppressant medications including cyclosporine, azathioprine, and prednisione. Unknown to the transplant physicians, the patient began taking allopurinol 300 mg daily, which was prescribed by the primary care physician for hyperuricemia, a condition associated with cyclosporine therapy. Allopurinol inhibits the metabolism of azathioprine by the enzyme xanthine oxidase, resulting in increased plasma concentrations and the potential for azathioprine toxicity. This is often seen as bone marrow depression and pancytopenia. This drug interaction led to a hospital stay of more than 30 days and $180,000. The hospital was reimbursed just under $32,000 (from Medicare) resulting in a net loss of almost $150,000. (McConnell, 2004; Horn & Hansten, 2006).
This interaction received much attention in the medical literature in the early 1970s. It doesn’t appear immediately; it is insidious and may manifest itself up to 30 or more days after co-administration. Further, this interaction usually isn’t noticed until the patient comes back for a follow-up appointment or a refill, or ends up in the emergency room with a bleeding episode or a severe infection.
We have come a long way since the early 1970s. With phenomenal advances in knowledge and the invasion of technology into our medical practices, a fundamental interaction like the one described above shouldn’t occur, right?
I admit that the simultaneous use of allopurinol and azathioprine isn’t one of the drug interactions I think about on a daily basis. And like many of you, I don’t see many transplant patients in my clinical practice. In fact, when I asked several primary care clinicians, I found very little immediate knowledge of this interaction. I also questioned several pharmacists who practice at one of the local chain pharmacies about this interaction and received some blank stares.
Perhaps I am too critical; I am sure there are many clinicians who are familiar with this interaction. But let’s be honest: somewhere there was a breakdown — more likely, multiple breakdowns — in the care delivery process.
The Breakdown
Did the primary care physician know this was a transplant patient? Did the patient tell the primary care physician which medications he was taking for the transplantation? Did the primary care physician use an electronic health record or e-prescribing tool? If so, was the program monitoring the interaction up-to-date and working properly? Did the pharmacy that filled the allopurinol prescription have a record of concurrent azathioprine use? If they had a record, did the pharmacist bypass the interaction alert to save time because “the darn thing pops up all of the time!”
As a clinician, it is my responsibility to be familiar with the diagnoses, therapies, and treatments administered to my patients. Did the pharmacist ask if there was any disease or treatments he or she should be aware of before filling the allopurinol prescription? Did the transplant team tell the patient to tell the pharmacist and other caregivers that he or she had received a transplant and was being treated with immunosuppressant medications?
If I am unfamiliar with a particular drug, disease state, therapy, or treatment, it is my responsibility to understand it before I administer a medication or advice to my patient. Being too busy isn’t a good excuse; neither is ignorance.
The Comfort Zone
Most likely, multiple breakdowns caused this unnecessary hospitalization, stress and anxiety to the patient and his or her family, and the cost borne by society. Patients need to be better educated and advised to be upfront with their care providers. This is especially true for those patients who have received transplants or have other disease states that primary care clinicians don’t regularly see nor treat. Additionally, patient care providers must be especially careful when treating or advising patients who have disease states they don’t see on a daily basis. And finally, providers should assure their drug interaction detection systems are updated, working properly, integrated into regular operations, and used by all clinical caregivers.
We still don’t have control over those patients who use multiple clinicians and pharmacies. We all know patients who get some of their medications from a specialty clinic, others from a community pharmacy, and still others through mail order. The possibility for significant interactions in these patients should put us all on guard.
Now, if we only had a nation-wide (or even a regional) network of standardized technologies where all clinical caregivers could access a patient’s medical and drug history, we would have the potential to eliminate problematic interactions. But that’s a discussion for another day…
Larry Pawola is associate professor in the College of Applied Health Sciences at the University of Illinois at Chicago and president of his own healthcare information technology and clinical services consulting firm, Lincolnshire Consulting Associates LLC. Pawola is a member of the Editorial Advisory Board for PSQH may be contacted at lpawola@uic.edu.
References
Horn, J., & Hansten, P. (2006). Old drug interactions harming new patients. Pharmacy Times. Accessed October 2, 2006, at http://www.pharmacytimes.com/Article.cfm?Menu=1&ID=3657.
McConnell, P. J. (2004). The $181,000 adverse drug reaction. Hospital Pharmacy, 39, 648-652.