Understanding Prescription Abandonment

The correlation between the amount of a patient’s copay and the likelihood of abandoning the prescription at the pharmacy.

Research resulting from our partnership with Harvard University and Brigham and Womens Hospital has drawn a lot of interest from the digital health care community, we think because it puts a spotlight on a very basic problem in patient care – the fact that many patients never pick up the medications that their doctors prescribe for them. While the problem of prescription abandonment has been a known issue to pharmacists for some time, the reasons behind this have never really been known.

A study published in the Annals of Internal Medicine – The Epidemiology of Prescriptions Abandoned at the Pharmacy -- is the first to systematically evaluate rates and predictors of prescription abandonment. Strikingly, researchers found a direct correlation between the amount of a patient’s out-of-pocket co-pay and the likelihood of abandonment. Patients having a co-pay of $50 were nearly four times more likely to abandon a prescription at a pharmacy than patients paying $10. We and others have noted previously the impact that out-of-pocket patient costs have on medication adherence, but this research shows us a new and important facet of this contributor to non-adherence. And the better we understand this, the better we and the rest of the health care system can help patients avoid the health deterioration and financial costs that often follow non-adherence. As Michael D. Murray of the Purdue University College of Pharmacy and the Regenstrief Institute and Jeff Harrison of the University of Auckland observed in an Annals of Internal Medicine editorial commenting on our findings, “the costs of abandoned and denied prescriptions include therapeutic failure, avoidable deterioration in health, and the resultant increased cost of health care.”

These findings were based on a review of all prescriptions dispensed at CVS Pharmacy locations between July 1, 2008 and September 30, 2008.  Of the prescriptions that were abandoned, more than half were never filled at any pharmacy, while some were filled at other pharmacies at a later date.  Overall, 3.27 percent of the prescriptions filled during this time period were never picked up – if that abandonment rate held true for the 3.6 billion prescriptions filled at all U.S. pharmacies in 2008, that means that approximately 110 million prescriptions were abandoned that year.

The study also found that e-prescriptions are 65 percent more likely to be left abandoned at a retail pharmacy by patients than are hand-written prescriptions.  But this higher abandonment rate, they noted, may simply be due to the fact that patients with written prescriptions must proactively bring the request for medications to the pharmacy. Patients with e-prescriptions are not required to take any step to begin the prescription filling process.  The rate of e-prescription abandonment may also appear high because pharmacies are better able to track these prescriptions. Paper prescriptions that are abandoned are never actually brought to a pharmacy, making them harder to track.

Seeking to help pharmacists anticipate which patients may be most likely to never pick up their medicine, the researchers from CVS Caremark, Harvard University and Brigham and Womens Hospital have presented the industry with their recommendations for identifying likely candidates for abandonment, which include: 

  • Reviewing the individual’s benefit plan and tiered co-pays.  The study said cost is the strongest predictor of abandonment. The data shows a 1.4 percent prescription abandonment rate for patients with co-pays of $10 or less, a 3.4 percent rate for patients with co-pays between $30 and $40 and a 4.7 percent rate for patients with co-pays of $50.

  • Understanding past pharmacy behavior. Patients with first-fill prescriptions are three times more likely to abandon prescriptions than those who are re-filling their medication.

  • Identifying the age of the patient. Younger patients more likely than older patients to abandon their medications.

  • Reviewing the drug class.  The study found that opiates, anti-platelets and statins were the least likely to be abandoned, while insulin and proton pump inhibitors were more likely to be abandoned.