Which statement about fondaparinux monitoring and reversal is true?

• A. Requires routine INR monitoring
• B. Requires no reversal agent and no routine monitoring
• C. Requires frequent aPTT monitoring
• D. Requires anti-Xa monitoring

Answer: (B)

Fondaparinux has a predictable dose–response and fixed dosing that do not require routine laboratory monitoring. There is no approved reversal agent for fondaparinux, so bleeding or overdose is managed supportively rather than with an antidote. In practice, INR is not used to monitor fondaparinux, and although aPTT can be variably prolonged, it is not used to guide dosing. Anti-Xa testing exists in specialized situations but is not part of routine monitoring. Dosing and monitoring decisions are instead guided by clinical bleeding risk and renal function, with dose adjustments needed in renal impairment.