Direct factor Xa inhibitors

They bind factor Xa themselves, with no need for antithrombin, and block it both free in the blood and inside the prothrombinase complex. Less prothrombin is converted to thrombin, so less fibrin is laid down and clots grow less. They have no direct effect on platelets, but they reduce the platelet aggregation that thrombin would trigger.

• RivaroxabanAlso licensed, together with aspirin, to lower the risk of heart attack, stroke and limb events in coronary or peripheral artery disease.
• ApixabanIn the main atrial fibrillation trial (ARISTOTLE) it caused less major and less intracranial bleeding than warfarin.
• EdoxabanIts boxed warning is unusual: in atrial fibrillation, very good kidney function (CrCl above 95 mL/min) lowers its blood levels and its benefit.

• Preventing stroke in nonvalvular atrial fibrillation
• Treating and preventing deep vein thrombosis
• Treating pulmonary embolism

• BleedingKnown forSerious
• Spinal or epidural hematoma after spinal proceduresSerious
• Clots and stroke if stopped earlySerious
• Anemia
• Abnormal liver tests, rarely hepatitis
• Rash
• Allergic reactions
• AngioedemaSerious
• Low platelet count
• Kidney injury (anticoagulant-related nephropathy)Serious

What the class has in common. Each drug's card has its own, and Known for marks what an exam expects you to know.

• No routine monitoring: PT, INR and aPTT change too little and too unevenly to measure their effect.
• Not recommended with prosthetic heart valves or triple-positive antiphospholipid syndrome.
• Drugs that strongly inhibit both P-gp and CYP3A4 raise their levels and bleeding risk; inducers such as rifampin lower them.
• Boxed warnings: stopping early raises the risk of clots, and spinal or epidural procedures risk a hematoma that can paralyze.

Written for biofideX in plain words, after checking these references:

• Rivaroxaban tablets: label (DailyMed)
• Apixaban tablets: label (DailyMed)
• Edoxaban tablets: label (DailyMed)
• Direct Factor Xa Inhibitor (NCI Thesaurus)
• Anticoagulant medicines (NHS)

For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.