Impact of the FDA Warning for Azithromycin and Risk for QT Prolongation on Utilization at an Academic Medical Center

Abstract

A US Food and Drug Administration (FDA) drug safety communication was released in March 2013, warning prescribers of the risk of QT prolongation associated with azithromycin. Overall azithromycin utilization and adherence to an inpatient QTc monitoring guideline during 8-month time periods before and after the warning were assessed to evaluate the impact of this warning on inpatient azithromycin utilization and QTc monitoring. Fifty-five patients were included in the prewarning time period and 50 were included in the postwarning period. A significant reduction in utilization in days of therapy per 1,000 patient days was observed (31.2 prewarning vs 17.5 postwarning, p < .001) in these groups. No changes in QTc monitoring among patients receiving azithromycin were identified. FDA warnings of severe, life-threatening toxicities can have a profound impact on utilization and prescribing of medications, however they may not necessarily change monitoring practices.

Do drug‐related safety warnings have the expected impact on drug therapy? A systematic review

“…All of the 70 publications included are observational studies based on routinely collected health data, which included health insurance or hospital records. Thus, no RCTs were found for the defined search period.…”

“…In 66 out of 72 studies, intended changes in drug therapy were investigated with different results regarding their effectiveness. Contents of the safety warnings were described as effective in 28 out of 72 studies . In 12 studies, the authors concluded that the content of the safety warnings investigated did not lead to a change in drug therapy .…”

“…In contrast, just 45% (17/38) of the studies in the “others” group were presented as ineffective or partially effective. But 53% (20/38) described an effective impact, and only 2% examined an unintended effect. Details of this group are shown in Data S2.…”

“…Unintended effects were examined in 15% 9,28,60,72,80 of these 34 studies. For space constraints, only the group of "psychotropic drugs" is shown inTable 2.3.3.2 | Results for the "others" groupIn contrast, just 45% (17/38)22,25,30,33,38,44,46,47,56,61,62,65,69,74,77,78,84 of the studies in the "others" group were presented as )[18][19][20]23,25,26,29,31,42,44,48,[50][51][52]58,64,67,68,71,73 described an effective impact, and only 2% 75 examined an unintended effect. Details of this group are shown in Data S2.…”

Covid-19 treatment update: follow the scientific evidence

“…The FDA issued a warning on May 17, 2012 on the risk of potentially fatal heart rhythm abnormalities associated with the drug. Employing a large claims database of over 12 million patients with greater than 23 million azithromycin prescriptions, Patel and colleagues [33] identified nearly 25% of patients were receiving another drug with QTc producing effects. The presence of pre-existing cardiac conditions was ~ 8.0%.…”