Please check your internet connection and try again.
# Apixaban (Eliquis)
## Overview
Apixaban is an oral, direct factor Xa inhibitor that prevents thrombus formation by inhibiting free and clot-bound factor Xa. It has high bioavailability and a rapid onset of action (1–3 hours).
## Primary Indications
* Reduction of risk of stroke/systemic embolism in non-valvular atrial fibrillation (NVAF).
* Treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE).
* Reduction in the risk of recurrent DVT and PE following initial therapy.
* Prophylaxis of DVT (which may lead to PE) following hip or knee replacement surgery.
## Adult Dosing
* **NVAF:** 5 mg PO BID. Reduce to 2.5 mg BID if at least two of the following: Age ≥80 years, Body weight ≤60 kg, or Serum creatinine ≥1.5 mg/dL.
* **Treatment of DVT/PE:** 10 mg PO BID for 7 days, followed by 5 mg PO BID.
* **Secondary Prophylaxis (post 6 months treatment):** 2.5 mg PO BID.
* **Prophylaxis post-orthopedic surgery:** 2.5 mg PO BID. Start 12–24 hours post-operatively. Duration: 12 days (knee) or 35 days (hip).
## Pediatric Dosing
**Not FDA-approved for pediatric use.** Dosing in pediatrics is off-label and varies significantly by institutional protocol, generally based on age and weight. Consult institutional hematology/pediatric guidelines or clinical trials (e.g., EINSTEIN-Jr) before prescribing.
## Dose Adjustments
* **Renal Impairment:** No dose adjustment needed for mild to moderate impairment. Not recommended in patients with CrCl <15 mL/min or on dialysis (limited clinical data).
* **Hepatic Impairment:** Avoid in severe hepatic impairment (Child-Pugh C). Use with caution in moderate impairment (Child-Pugh B).
## Contraindications
* Active pathological bleeding.
* Hypersensitivity to apixaban.
* Prosthetic heart valves (significantly increased risk of stroke/thrombosis).
## Adverse Effects
* Major bleeding (gastrointestinal, intracranial, epistaxis).
* Anemia.
* Nausea.
* Hypersensitivity reactions.
## Key Drug Interactions
* **P-gp and Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin, ritonavir):** Increase apixaban exposure; decrease dose to 2.5 mg or avoid if already on 2.5 mg.
* **P-gp and Strong CYP3A4 inducers (e.g., rifampin, phenytoin, carbamazepine, St. John’s Wort):** Decrease apixaban exposure; avoid concomitant use.
* **Anticoagulants/Antiplatelets/NSAIDs:** Increase risk of bleeding; monitor closely.
## Monitoring
* **Baseline:** CBC, CrCl (Cockcroft-Gault), LFTs.
* **Ongoing:** Monitor for clinical signs of bleeding, hemoglobin/hematocrit, and renal function (periodically or if clinically indicated).
* **Note:** Routine coagulation monitoring (PT/INR, aPTT) is neither reliable nor required.
## Clinical Pearls
* **Reversal:** Andexanet alfa is the specific reversal agent for life-threatening or uncontrolled bleeding.
* **Missed Dose:** Take as soon as remembered on the same day; do not double the dose.
* **Transitioning:** Specific crossover protocols exist for switching to/from warfarin or parenteral anticoagulants; verify via hospital-specific protocols.
* **Crushability:** Tablets can be crushed and suspended in water, D5W, or apple juice for NG tube administration.
***
**Disclaimer:** This information is for educational purposes only. Drug information is subject to change. Always verify current prescribing information, institutional protocols, and specific patient contraindications via comprehensive clinical databases (e.g., Lexicomp, Micromedex) or the manufacturer's package insert before prescribing.
