Pharmacologic and liability considerations of therapeutic interchange with low-molecular-weight heparins

Therapeutic interchange (TI), a formulary management process, is used by health care systems to help contain medication costs. A scientifically defensible and pharmacoeconomically beneficial TI program adheres to rigorouscriteria enforced by an institution's Pharmacy and Therapeutics Committee. In situations where adherence to essential criteria is not mandated, TI may not produce the intended clinical and economic outcomes, and in practice may have legal implications. Appropriate application of TI has been described within the position statements of certain health care organizations and associations. Due to the high cost and frequent use of low-molecular-weight heparins (LMWHs), health care institutions have identified this pharmacologic class as a potential target for TI. Currently, the application of the TI process to LMWHs is questionable. This paper reviews the TI process and explores its controversial role in the formulary management of LMWHs.