Slide Presentation from the AHRQ 2007 Annual Conference

The Prescribing Cascade

Flowchart showing Drug 1 leading to an ADE leading to Drug 2.

Notes:

This figure describes The Prescribing Cascade: Drug 1 causes an adverse drug reaction (ADR) that leads to prescription of Drug 2. As a general principle, the prescription of drugs solely for the purpose of treating drug side effects should be avoided in elderly patients. Now I can be convinced that in some rare circumstances, after a careful evaluation of the benefits vs the risks of the offending agent, an appropriate decision could be made by the prescriber to continue Drug 1 and prescribe Drug 2 to treat Drug 1's side effects. However, what worries me is when little if any thought is given before prescribing Drug 2—no consideration of the absolute need for Drug 1, no consideration of the possibility of a reduction in dose, no consideration of an alternative therapy that may have a lower risk of adverse effects. Most disturbing of all would be the prescription of Drug 2 without recognition that the condition being treated is an adverse drug reaction. The obvious worry for the elderly is that drug-induced symptoms might be misinterpreted as indicating the presence of a new disease or incorrectly attributed to the aging process itself.