Medication Safety 101: Adverse Drug Events

It cannot be debated: medicine, specifically prescription medication, has revolutionized and enhanced the way healthcare professionals all over the world care for their patients. This is nothing new. In fact, medication has helped improve patient health tracing all the way back to circa 2112 BC when the first medical prescriptions appeared in ancient Sumer, the earliest known civilization in the historical region of southern Mesopotamia.[1]

However, and despite literally thousands of years of success stories, there is another side to prescription drug use, adverse drug events (ADEs). Today the healthcare community is looking for ways to combat ADEs and how pharmacists—specifically—can step in to turn the tide and prevent them.

What is an ADE?

An ADE is defined as an injury resulting from medication taken at normal doses.[2]



It is important to note that ADEs are not confined to one isolated patient demographic or care setting; they can happen to anyone who takes medication and they can happen anywhere, from hospitals to home.

ADEs in inpatient settings (annually):

  • Account for 1 in 3 of all hospital adverse drug events
  • Account for around 2 million hospital stays
  • Prolong hospital stays by 1.7 to 4.6 days

ADEs in outpatient settings (annually):

  • Account for more than 3.5 million physician office visits
  • Account for around 1 million emergency department visits
  • Account for around 125,000 hospital admissions

While the exact number of ADEs is not certain, they have been estimated to be underreported by up to 90%. By some estimates, if it were a disease, ADEs would be the third leading cause of death in the United States.[3][4][5]

The question is why ADEs have become so prevalent.


Today’s society heavily relies on medication to treat multiple diseases. Treating multiple diseases requires taking multiple medications often prescribed by multiple providers. No segment of the population exemplifies this scenario more than older Americans. Consider this report (PDF) published by the Center for Disease Control and Prevention, which found that about a third of American adults aged 60 to 79 used five or more prescription drugs…in the past 30 days!

Patients taking multiple drugs for multiple diseases prescribed by multiple medical providers inherently increases the likelihood of gaps in care. The lack of medication care coordination can lead to patients taking medications that do not interact well with one another and trigger an ADE. What further complicating this issue is the tendency for the effects of an ADE (e.g. tiredness, dizziness, nausea) to be misdiagnosed as new symptoms of a new disease, leading to yet another prescribed medication.

Remember: a large majority of ADEs are preventable. Doing so would not only directly lead to saving patient lives, but also to a safer and higher quality of healthcare services, reduced healthcare costs, and improved health outcomes.[6] Still, each day patients are continually and unknowingly prescribed medications that could trigger an ADE. While changing the prescribing practice of doctors could help, it is not the answer. The answer is to equip and empower medication experts—pharmacists—with science-based technologies and solutions they can use to help prevent ADEs. Consumers who seek their consultation can help assure their and their loved ones’ medication safety