Adverse Events Associated with Prescribing Diuretics After Calcium-Channel Blockers

Lower-extremity edema is a well-known side effect of calcium-channel blockers (CCBs). Although diuretics sometimes are prescribed to manage this edema, they are typically ineffective, as CCB-related edema probably is caused by arteriolar vasodilation rather than excess plasma volume (NEJM JW Gen Med Apr 1 2020 and JAMA Intern Med 2020; 180:643). This series of prescriptions represents a “prescribing cascade”: the addition of a second, often unnecessary medication to manage an adverse drug effect.

To study rates of serious adverse events associated with this specific prescribing cascade, researchers in Ontario, Canada, used local health databases to follow ≈40,000 older adults (age, >65; no history of heart failure or advanced renal disease) …