Rivaroxaban
Xarelto
Direct oral anticoagulant — factor Xa inhibitor
Directly binds and inhibits free + clot-bound factor Xa. Predictable, fixed dosing, no routine monitoring.
Indications
- •AF stroke prevention
- •VTE treatment + prevention
- •Post-ACS (low dose + ASA)
- •Peripheral artery disease
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| AF | 20 mg PO daily with food (15 mg if CrCl 15–50) | — |
| VTE treatment | 15 mg PO BID × 21 days, then 20 mg daily | — |
Pharmacokinetics
Onset 2–4 h. Half-life 5–9 h (11–13 h elderly). Take with food for absorption. Partial renal + hepatic clearance.
Side effects
- !Bleeding (GI most common)
- !No routine monitoring
- !Cannot use anti-Xa unless calibrated for rivaroxaban
Contraindications
- ×CrCl <15
- ×Severe hepatic disease (Child-Pugh B/C)
- ×Mechanical valves
- ×Active bleeding
Reversal / antidote
Andexanet alfa (Andexxa) — specific; 4-factor PCC (Kcentra) as alternative
Clinical pearls
- ★ASRA neuraxial: hold 72 h (3 days) before neuraxial block/catheter removal; restart 6 h after.
- ★Take the 15/20 mg dose WITH FOOD — bioavailability drops markedly fasting.
- ★Reversal: andexanet alfa if available, otherwise 4F-PCC 50 units/kg.
Other drugs in Coagulation Related
- Heparin (unfractionated)
Activates antithrombin → inactivates IIa (thrombin) and Xa.
- Tranexamic Acid (TXA)
Reversibly binds plasminogen, blocking conversion to plasmin → preserves fibrin clot.
- Protamine Sulfate
Strongly basic (positive-charge) protein binds to highly acidic (negative-charge) heparin → inactive ionic complex → renal excretion. 1 mg protamine neutralizes ~100 units heparin.
- DDAVP (Desmopressin)
Selective V2 agonist (renal water retention + Factor VIII/vWF release from endothelial Weibel-Palade bodies). NO V1 vasopressor activity at therapeutic dose.
- Warfarin
Inhibits vitamin K epoxide reductase (VKORC1) → depletes reduced vitamin K → ↓ synthesis of factors II, VII, IX, X and proteins C/S. Full effect takes days (waits for existing factor decay).
- Enoxaparin
Antithrombin-mediated inhibition, weighted toward factor Xa over IIa (~3.8:1). More predictable than UFH — no routine monitoring.
- Dalteparin
Antithrombin-mediated factor Xa > IIa inhibition. Similar profile to enoxaparin; preferred LMWH in cancer-associated VTE (CLOT trial).
- Tinzaparin
Antithrombin-mediated factor Xa > IIa inhibition; higher mean molecular weight than enoxaparin (anti-Xa:IIa ~1.9:1).
Browse all classes: /reference/drugs
Suggested reading
- •Miller's Anesthesia, 9e
- •FDA package insert
- •ASRA regional anesthesia in the anticoagulated patient guidelines, 2018
