One of the most important yet often overlooked concepts in pharmacology is the prescribing cascade. It occurs when a new medication is prescribed to treat a side effect caused by another drug, without realizing that the first medication is the root cause. This leads to a chain reaction of additional prescriptions, unnecessary complexity, and often, new adverse effects.



Prescribing cascades can sneak up on even the most careful clinicians. A patient develops a new symptom after starting a medication—perhaps swelling, dizziness, or urinary changes—and instead of identifying the drug as the culprit, another medication is added to manage the symptom. Over time, this cycle contributes to polypharmacy, drug interactions, and reduced quality of life.



These cascades are particularly concerning in older adults, where multiple comorbidities and high medication counts make it easy for adverse effects to be misinterpreted as new conditions. But they can occur at any age and in any clinical setting.



The key to preventing prescribing cascades is maintaining a critical mindset:




Assume any new symptoms could be an adverse effect.



Review the timing of medication changes relative to the onset of symptoms.



Consider deprescribing or adjusting doses before adding new drugs.



Encourage thorough medication reconciliation and communication across providers.




Recognizing and interrupting the prescribing cascade is one of the simplest and most impactful ways we can improve medication safety. In this podcast, I share some of my favorite real-world examples that illustrate just how easily these cascades can happen.