The most significant side effect of Xarelto (rivaroxaban) 20 mg is bleeding, which ranges from minor bruising and nosebleeds to serious internal hemorrhage. Because this medication works by blocking a key clotting factor in your blood, every side effect traces back to that central mechanism: your blood doesn’t clot as easily as it normally would. Beyond bleeding, some people experience nausea, dizziness, or muscle pain, though these are generally less common and less dangerous.
Bleeding: The Primary Risk
Bleeding is by far the most important side effect to understand. In a real-world registry tracking patients on rivaroxaban, about 43% reported at least one bleeding event while on the medication. The vast majority of those were minor, like small bruises, bleeding gums, or cuts that took longer than usual to stop. About 35% of bleeding events were classified as “clinically relevant but not major,” meaning they were noticeable and sometimes required medical attention but weren’t life-threatening. Roughly 6% were considered major bleeding events.
The annualized rate of major bleeding runs between 3 and 4 events per 100 patients per year, depending on the condition being treated. Patients taking Xarelto for blood clots in the legs or lungs had a slightly higher rate (4.1 per 100 patient-years) compared to those taking it for atrial fibrillation (3.1 per 100 patient-years). Major bleeding typically means bleeding that requires a blood transfusion, causes a significant drop in blood counts, involves a critical location like the brain or stomach, requires surgical intervention, or is fatal.
Gastrointestinal bleeding is one of the more common forms of serious bleeding. You might notice dark or tarry stools, blood in your urine, vomiting blood, or coughing up blood. These are signs to get medical help immediately.
Everyday Side Effects
Outside of bleeding, the side effects people notice in daily life tend to be milder. These can include nausea, stomach discomfort, dizziness, headache, and muscle or joint pain. Some people also report itching or a skin rash. These effects vary widely from person to person, and many people take Xarelto without experiencing anything beyond occasional easy bruising.
Hair loss has been reported in isolated cases, though a formal investigation by New Zealand’s drug safety authority found no demonstrated link between rivaroxaban and alopecia. A monitoring period turned up no additional cases, so this appears to be rare and unconfirmed.
Liver Effects
Xarelto is processed partly through the liver, and postmarketing reports have included cases of jaundice (yellowing of the skin or eyes), liver inflammation, and bile flow problems. These are uncommon but worth knowing about. If you notice yellowing skin, unusually dark urine, or persistent upper-right abdominal pain, those warrant prompt medical attention. People with moderate or severe liver disease generally should not take Xarelto, as drug levels in the blood can more than double in people with compromised liver function.
Why Taking It With Food Matters
The 20 mg dose has a quirk that directly affects how well it works: when taken on an empty stomach, your body only absorbs about 66% of the medication. Taking it with food increases absorption by roughly 39%, with peak blood levels jumping by 76%. This isn’t a minor difference. If you take the 20 mg tablet without food, you’re getting meaningfully less of the drug than intended, which could reduce its effectiveness at preventing blood clots. Always take the 20 mg dose with a meal.
Medications That Raise Your Risk
Certain common medications significantly increase bleeding risk when combined with Xarelto. The NHS specifically warns against taking ibuprofen or aspirin while on rivaroxaban unless your doctor has explicitly approved it. Both are NSAIDs (non-steroidal anti-inflammatory drugs), and they interfere with your blood’s ability to clot through a different pathway than Xarelto does. The combination hits your clotting system from two directions at once.
Other medications to be cautious with include other blood thinners like warfarin or injectable anticoagulants, and antiplatelet drugs. If you’re taking any over-the-counter pain relievers regularly, make sure your prescriber knows. Acetaminophen (Tylenol) is generally the safer choice for pain relief while on Xarelto, though it’s worth confirming with your prescriber if you use it frequently.
The FDA’s Boxed Warnings
Xarelto carries two FDA boxed warnings, the most serious type of safety alert.
The first warns against stopping the medication abruptly. Discontinuing any blood thinner prematurely raises the risk of blood clots, stroke, and other thrombotic events. If you need to stop Xarelto for any reason other than active, dangerous bleeding, your doctor will typically bridge you to another anticoagulant to maintain protection.
The second warning concerns spinal and epidural procedures. People who receive spinal anesthesia or undergo spinal puncture while on Xarelto face a risk of blood collecting near the spinal cord (spinal or epidural hematoma). This can cause long-term or permanent paralysis. Several factors raise this risk further:
- Indwelling epidural catheters left in place during treatment
- Other medications that affect clotting, including NSAIDs and antiplatelet drugs
- History of spinal surgery or spinal deformity
- Repeated spinal punctures or traumatic needle placement
If you have any spinal procedure planned, your medical team needs to know you’re taking Xarelto so they can time the procedure safely.
What Happens in a Bleeding Emergency
Unlike older blood thinners such as warfarin, Xarelto historically had no way to be quickly reversed in an emergency. That changed with the FDA approval of a reversal agent (andexanet alfa, brand name Andexxa), which is specifically approved for rivaroxaban and one other similar blood thinner. It works by binding to the drug and neutralizing its effect on the clotting system. This medication is reserved for life-threatening or uncontrolled bleeding situations in hospital settings, but its existence means that emergency reversal is now possible if you experience a serious bleeding event.
Xarelto’s half-life is roughly 5 to 9 hours in healthy adults, meaning it clears your system relatively quickly compared to some older anticoagulants. After you stop taking it, most of the drug’s blood-thinning effect wears off within 24 hours, though this can take longer in people with reduced kidney function.