Apixaban

Is apixaban safe?

For most people who need a blood thinner, apixaban is one of the safer choices available, but no anticoagulant is low-risk. Its job is to slow clotting, and the price of that is bleeding. In ARISTOTLE, the trial of 18,201 people with atrial fibrillation that led to its approval, major bleeding happened at 2.13% a year on apixaban against 3.09% on warfarin. Bleeding into the brain was 0.33% against 0.82%.

We score apixaban 64. That is well above warfarin's 49, mainly because it bleeds less and needs no blood tests, and well below everyday medicines such as atorvastatin. A middling score reflects the care it needs. It is not a reason to stop: stopping without a plan raises the risk of stroke, which is one of the two parts of its boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary.

How does apixaban compare with warfarin?

ARISTOTLE (NEJM, 2011) compared apixaban 5 mg twice a day with warfarin at a target INR of 2 to 3. The results:

Outcome, per year	Apixaban	Warfarin
Stroke or systemic embolism	1.27%	1.60%
Major bleeding	2.13%	3.09%
Bleeding into the brain	0.33%	0.82%
Fatal bleeding	0.06%	0.24%
Death from any cause	3.52%	3.94%

Stomach and gut bleeding was about the same on both (0.83% against 0.93% a year). That bleeding advantage is not shared by every newer blood thinner. In its own trial against warfarin, rivaroxaban cut brain and fatal bleeds but not overall major bleeding. The two drugs were never compared directly in these trials, so the comparison is indirect.

The boxed warning

The current US label carries a two-part boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary:

• Stopping early. Stopping any oral anticoagulant without another one in place raises the risk of clots. In the atrial fibrillation trials, strokes rose during the switch from apixaban to warfarin.
• Spinal and epidural bleeding. In people having a spinal or epidural anaesthetic or a lumbar puncture, a blood clot can form around the spinal cord and cause lasting paralysis. Epidural catheters, NSAIDs, other blood thinners and past spinal surgery raise the risk.

Neither warning is about everyday use, but both affect real decisions: planned surgery, an injection into the spine, or running out of tablets.

Doses and missed doses

US label doses for adults:

• Atrial fibrillation: 5 mg twice a day, or 2.5 mg twice a day if two of these apply: aged 80 or over, weight 60 kg or less, serum creatinine 1.5 mg/dL or higher.
• Treatment of a DVT or pulmonary embolism: 10 mg twice a day for 7 days, then 5 mg twice a day; 2.5 mg twice a day to prevent a recurrence after at least 6 months.
• After hip or knee replacement: 2.5 mg twice a day for 35 or 12 days.

Apixaban wears off within about a day, so it protects only while you keep taking it. A missed dose should be taken the same day, never doubled. An accidental extra dose rarely causes trouble on its own, but a large overdose or one taken by a child needs urgent care: call Poison Control (1-800-222-1222) in the US or NHS 111 in the UK. Activated charcoal given within a few hours cuts absorption.

Interactions to know

Apixaban has far fewer interactions than warfarin and none with food. Those that matter:

• Ketoconazole, itraconazole and ritonavir raise levels; the label halves the dose or avoids the combination.
• Rifampin, carbamazepine, phenytoin and St John's wort lower levels and can leave you unprotected.
• Aspirin, clopidogrel, NSAIDs such as ibuprofen and naproxen, and SSRI or SNRI antidepressants add to bleeding risk. In ARISTOTLE, aspirin nearly doubled major bleeding on apixaban, from 1.8% to 3.4% a year.

What if serious bleeding happens?

This changed recently in the US. The specific antidote, andexanet alfa (Andexxa), was withdrawn from the US market on 22 December 2025 after the FDA concluded its risk of clots outweighed its benefits. It is still sold in the UK and the EU. US hospitals now treat life-threatening bleeding with prothrombin complex concentrate and supportive care. Vitamin K, the antidote for warfarin, does not work on apixaban.

Who should be careful

• People with mechanical heart valves or triple-positive antiphospholipid syndrome: the label does not recommend apixaban.
• Anyone booked for surgery, spinal anaesthesia or an epidural: tell the team well in advance.
• Older people, those with low body weight or kidney disease, and anyone on aspirin or NSAIDs.
• Pregnancy and breastfeeding need a specialist decision.

Carry an anticoagulant alert card, and get urgent help after a head injury, for black stools or for bleeding that will not stop. Talk to your doctor or pharmacist before any change.

How we scored it

Dependence (98) and track record (85) are strong. The boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary keeps regulatory warnings at 40, and bleeding holds serious side effects at 55, though both reflect a clearly better record than warfarin. Interactions (55) and overdose marginOverdose marginHow far a normal dose is from a harmful one. A wide margin means an accidental extra dose is unlikely to cause serious harm.More in the glossary (60) are moderate: fewer interactions than warfarin, but no specific US antidote since December 2025.