Rivaroxaban vs. apixaban in short bowel syndrome: a focused clinical pharmacology review.

INTRODUCTION: Short bowel syndrome (SBS) substantially alters nutrient and drug absorption and frequently necessitates long-term parenteral nutrition, increasing thrombotic risk. Indications for long-term anticoagulation such as atrial fibrillation or venous thromboembolism are common in this population. Because gastrointestinal anatomy and physiology are markedly distorted, the pharmacokinetics of direct oral anticoagulants (DOACs) may become unpredictable, creating uncertainty in drug selection and dosing.

AREAS COVERED: This review compares pharmacokinetic and clinical evidence for rivaroxaban and apixaban, the two DOACs most often used in SBS. Literature from pharmacology studies, case reports, prospective cohorts, and emerging population pharmacokinetic analyses was examined. Relevant literature was identified through searches of PubMed and Embase up to 1 November 2025.

EXPERT OPINION: Rivaroxaban exhibits food-dependent, dissolution-limited absorption in the stomach and proximal small intestine, and systemic exposure appears more sensitive to residual bowel length. Apixaban demonstrates linear, food-independent pharmacokinetics and generally preserved absorption in stable SBS, enabling concentration-guided dose adjustment when needed. Both agents can be effective in selected patients, but apixaban offers greater pharmacokinetic robustness in the context of altered intestinal anatomy or inconsistent oral intake. Early anti-Xa - based monitoring is advisable for either drug to confirm adequate absorption.