Just 23% of older adults in the ED gave a medication list that mirrored pharmacy records, according to the results of an analysis.1

More than half the patients omitted antibiotics they were taking at the time of the visit. “Not knowing about a medicine can lead to dangerous therapy or misdiagnosis,” says Daniel Pallin, MD, MPH, a Cambridge, MA-based EP and legal consultant. These are some examples of how knowing a patient’s medications can prevent bad outcomes:

The medication list reveals most of the patient’s chronic medical conditions. “For example, a patient on a high dose of a diuretic, a beta-blocker, and an ACE inhibitor should be presumed to have congestive heart failure, and caution is warranted with fluid boluses,” Pallin explains.

A medication can be the cause of the emergency. If a patient taking an ACE inhibitor presents with angioedema, there is a strong likelihood the ACE inhibitor is the cause. In that case, the patient should receive no treatment at all other than intubation, if needed.

“Many emergency providers may not know that lamotrigine, a very widely used drug, can cause a dangerous, progressive, allergic reaction, and must be stopped if the patient presents with a rash soon after starting to take it,” Pallin adds.

The medication list can indicate necessary emergency treatments. “Consider the millions of patients taking factor Xa inhibitors,” Pallin says.

Most of those patients exhibit nothing abnormal on coagulation studies, so ED providers might never know they are anticoagulated without looking at the medication list. “Right when they hit the door, if there’s hemorrhage, you need to get the andexanet or prothrombin complex concentrate ordered,” Pallin explains.

A complete medication list can shed light on the patient’s presenting symptoms and prevent misdiagnosis. An example is a patient who was treated with a checkpoint inhibitor, either currently or in the past year.

“If you don’t know about that therapy, you won’t make the diagnosis,” Pallin observes. “These agents are widely used, and the numerous side effects are very common.”

The patient’s current medication list can contraindicate certain therapies. “The drug most commonly implicated in adverse outcomes is warfarin,” Pallin reports.

Many drugs increase or decrease warfarin’s effects. These include trimethoprim-sulfamethoxazole and fluoroquinolones, which are commonly administered in the ED.

Sometimes, patients cannot give the information because they cannot recall all their medications, and there are no records in the system. Talking about the patient’s complaint, or asking about broader categories of medications, might elicit more specific details, says Daniel LaLonde, MD, medical director of the ED at Ascension Providence in Southfield, MI.

If someone presents with head trauma, asking about “blood thinners” can elicit a history of antiplatelets or anticoagulants. “A focused medication history may expand your differential,” LaLonde says. If a patient with back pain is taking warfarin, the EP considers the possibility of retroperitoneal hemorrhage.

Documentation of pertinent negatives is important for the defense of a malpractice claim. For a young woman with pleuritic chest pain, LaLonde says to specifically note the patient is not on birth control (if that is the case).

Blood tests might be the only way to definitively confirm whether patients are taking a particular drug. For instance, if a patient presents with refractory atrial fibrillation and a questionable history of taking digoxin, the level can be checked in this manner.

“Most anti-epileptics can also be checked in terms of their therapeutic levels, as well as drugs related to toxic metabolites, such as salicylates and acetaminophen,” LaLonde says.

Medication history becomes extremely important when using alteplase is considered for patients with acute ischemic cerebrovascular accident. “There are plenty of contraindications to this drug, including the use of novel anticoagulants,” LaLonde notes.

If the patient arrives with a significant aphasia, the EP should ensure the patient is not on a novel anticoagulant before giving alteplase over concerns about increased risk of hemorrhage.

Incomplete medication lists also are dangerous for anyone discharged with pain medications. “There is a black box warning regarding the concomitant use of benzodiazepines and opioids,” LaLonde says. If no one obtains a complete medication history, “you might be sending someone home with the potential for sedation or respiratory depression,” he adds.

How far are providers legally obligated to go to be sure the medication history is correct and complete? If a patient has known atrial fibrillation but no available medication list, it is incumbent on the provider to find out what anticoagulant the patient is taking for the atrial fibrillation before prescribing a contraindicated drug, according to Pallin. If the patient arrives alone with altered mental status and the medications are readily available in the EHR, a plaintiff attorney would argue a reasonable EP would have accessed the medication history. In that kind of case, says Pallin, “it’s harder to defend against negligence if there’s a medication side effect or a medication-related diagnosis.”

Generally speaking, ED providers are legally obligated to investigate and act on information that is reasonably accessible to them. “If the information about medication history is available with the click of a mouse, then there is a duty of care to review that information and use it in a treatment plan,” says Kenneth N. Rashbaum, JD, a partner at New York City-based Barton. “Too busy to check” is not much of a defense for providers. “Of course, that presumes the information is in fact in the EMR,” Rashbaum observes.

If the patient was never seen at the ED or hospital, there may be no medication history in the system. Juries are going to expect that ED providers tried to obtain the information from other sources. If there is no evidence providers tried, says Rashbaum, “it is extremely difficult for the defense to overcome if that failure leads to adverse reactions to medications given in the ED, or on the floor, or other medical issues with the patient.”

Documented efforts to secure a complete medication history helps the defense — providers asked the patient, friends, or family; they contacted the patient’s other doctors or pharmacy. As for the EP’s legal obligations, “this is a complex issue, and one that has not been well-litigated at the trial or appellate court levels,” Rashbaum says.

ED clinicians are expected to review information that is reasonably accessible to them. “This was the standard of care in the paper chart days, too, but then ‘reasonably accessible’ was more important,” Rashbaum recalls.

That is because the patient may have been seen at disparate locations, and it was not practical to gather all those paper charts. If the patient’s entire medical history is available electronically, then the standard of care requires ED providers to review it, says Rashbaum, unless there are compelling reasons not to (e.g., a code or some other urgent or emergent event).

Sometimes, the problem is the medication history is not accessible because it is contained in a different system. “Defense counsel, then, should be prepared to defend the failure to review the EMR on the basis of exigent circumstances, lack of interoperability, or causation, that nothing in the EMR would have changed the treatment or outcome,” Rashbaum says.


  1. Goldberg EM, Marks SJ, Merchant RC, et al. How accurately do older adult emergency department patients recall their medications? Acad Emerg Med 2020; May 21;10.1111/acem.14032. doi: 10.1111/acem.14032. [Online ahead of print].