Apixaban

Generic Name

Apixaban

Brand Name

Eliquis

Drug Class

Direct oral anticoagulant

Selective, reversible, direct Factor Xa inhibitor

Antithrombotic agent

Mechanism of Action

Apixaban inhibits Factor Xa, a key component in the coagulation cascade responsible for converting prothrombin to thrombin

By blocking both free and clot-bound Factor Xa, it prevents thrombin generation, inhibits fibrin clot formation, and disrupts thrombus development

Does not require antithrombin III for activity

Has no effect on platelet aggregation directly

Indications

Approved Uses

Prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation

Treatment of deep vein thrombosis (DVT)

Treatment of pulmonary embolism (PE)

Prevention of recurrent DVT and PE

Prophylaxis of DVT following hip or knee replacement surgery

Off-label Uses

Management of cancer-associated venous thromboembolism

Left ventricular thrombus (alternative to warfarin)

Post-operative atrial fibrillation management

Thromboprophylaxis in COVID-19 with elevated thrombotic risk

Mechanical heart valves not recommended

Dosage and Administration

Atrial Fibrillation

5 mg orally twice daily

Reduce to 2.5 mg twice daily in patients meeting two of the following: age ≥80 years, body weight ≤60 kg, serum creatinine ≥1.5 mg/dL

Treatment of DVT/PE

10 mg twice daily for 7 days, followed by 5 mg twice daily

Extended prophylaxis: 2.5 mg twice daily after ≥6 months of treatment

Postoperative Thromboprophylaxis

2.5 mg orally twice daily

Start 12 to 24 hours post-surgery

Duration: 12 days (knee replacement), 35 days (hip replacement)

Missed Dose

If a dose is missed, take it as soon as possible on the same day

Do not double the next dose

Renal Impairment

Mild to moderate: no adjustment needed

Severe renal impairment or on dialysis: use 2.5 mg twice daily if other criteria are met

Caution in CrCl <15 mL/min

Hepatic Impairment

Avoid in severe hepatic impairment

Caution in moderate impairment

Pharmacokinetics

Bioavailability ~50%

Time to peak concentration: 3 to 4 hours

Half-life: 9 to 14 hours

Protein binding: 87%

Metabolism: CYP3A4, CYP1A2, and SULT enzymes

Excretion: 25% renal, 75% fecal and biliary

Contraindications

Active pathological bleeding

Severe hypersensitivity to apixaban or formulation components

Hepatic disease associated with coagulopathy and clinically relevant bleeding risk

Lesions at increased risk of bleeding such as peptic ulcers or vascular aneurysms

Use with other anticoagulants unless transitioning

Warnings and Precautions

Discontinuation increases risk of thromboembolic events

Spinal or epidural hematoma risk in patients undergoing neuraxial anesthesia or spinal puncture

Not recommended in patients with mechanical heart valves

Caution in elderly, underweight, or impaired renal function

No routine INR monitoring required, but assess renal function periodically

Avoid abrupt withdrawal unless clinically indicated

Risk of bleeding may be increased with other agents affecting hemostasis

No reversal of antiplatelet activity; a reversal agent for anticoagulation exists for emergency use

Adverse Effects

Common

Nasal bleeding

Bruising

Gastrointestinal bleeding

Hematuria

Hemoptysis

Menorrhagia

Injection site bleeding (post-surgery use)

Nausea

Less Common

Anemia

Hypotension

Headache

Dizziness

Elevated liver enzymes

Rash

Serious

Intracranial hemorrhage

Gastrointestinal hemorrhage

Retroperitoneal bleeding

Spinal or epidural hematoma leading to paralysis

Fatal bleeding events

Surgical site bleeding requiring re-operation

Pregnancy and Lactation

Pregnancy

Use only if potential benefit justifies fetal risk

Avoid in late pregnancy due to bleeding risk

Not enough data on teratogenicity or miscarriage

Lactation

Unknown if excreted in human milk

Avoid breastfeeding or choose alternative anticoagulation

Drug Interactions

CYP3A4 and P-gp Inhibitors (e.g. ketoconazole, ritonavir, clarithromycin)

Increase apixaban exposure

Avoid or reduce dose if co-administered

CYP3A4 and P-gp Inducers (e.g. rifampin, carbamazepine, phenytoin, St. John’s Wort)

Decrease apixaban levels and efficacy

Avoid combination

Antiplatelets (e.g. aspirin, clopidogrel)

Increased bleeding risk

Use cautiously with monitoring

NSAIDs

Additive bleeding risk

Avoid unless necessary

Other Anticoagulants (e.g. heparin, warfarin, dabigatran)

Avoid unless transitioning between therapies

SSRIs/SNRIs

Potential increased bleeding due to platelet dysfunction

Use with caution

Monitoring Parameters

Signs of bleeding: bruising, hematuria, black stools

Hemoglobin and hematocrit levels

Renal function periodically

Signs of thromboembolic events in case of withdrawal

Liver function in long-term use

Counseling Points

Take regularly at the same time each day

Swallow whole with water, with or without food

Do not discontinue unless advised by a healthcare professional

Report signs of unusual bleeding or bruising immediately

Inform all healthcare providers, including dentists, that you are taking apixaban

Avoid over-the-counter NSAIDs or aspirin unless directed

Not interchangeable with warfarin dosing; no INR monitoring needed

Store at room temperature, away from moisture and heat

Do not use if tablet is chipped or broken

If surgery or dental procedures are planned, inform your physician to manage interruption of therapy

Comparative Notes

Apixaban vs Rivaroxaban

Apixaban is taken twice daily, while rivaroxaban is once daily

Apixaban has lower GI bleeding risk and more stable plasma concentration

Rivaroxaban has higher peak-to-trough variability

Apixaban vs Warfarin

Apixaban requires no INR monitoring, has fewer food/drug interactions, and offers more predictable anticoagulation

Warfarin has a longer half-life, is reversible with vitamin K, and is preferred in patients with mechanical valves or severe renal disease

Apixaban vs Dabigatran

Dabigatran is a direct thrombin inhibitor

Apixaban has fewer GI side effects and does not require acidic environment for absorption

Both have specific reversal agents

Regulatory Status

Prescription-only medicine

Approved for oral use in adults

Included in national and international guidelines for stroke prevention and VTE management

Available in 2.5 mg and 5 mg film-coated tablets

Classified as a high-alert medication in some safety frameworks due to bleeding risk