Key takeaways:
Pradaxa (dabigatran) is a blood thinner that helps treat and prevent blood clots. The most common Pradaxa side effects are heartburn, upset stomach, and minor bleeding.
Mouth or throat ulcers can occur if you don’t take Pradaxa capsules as directed, with a full glass of water.
More serious Pradaxa side effects include severe bleeding, blood clots, or complications during certain spinal procedures. Be sure to take Pradaxa as directed, and don’t stop taking it on your own. Seek emergency care if signs or symptoms of serious side effects occur.
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Pradaxa (dabigatran) is a blood thinner that helps prevent unwanted blood clots. It belongs to a group of medications called direct oral anticoagulants (DOACs). DOACs are often considered safer and more effective than older blood thinners, such as warfarin (Coumadin, Jantoven). But Pradaxa still has some side effects to be aware of while you’re taking it. Here’s what you should know.
Pradaxa side effects at a glance
Below is a list of Pradaxa side effects reported in clinical studies. Keep in mind that other side effects are possible. So be sure to reach out to your healthcare team about any concerning side effects that occur while taking Pradaxa, even if they aren’t listed below.
Mild Pradaxa side effects:
Minor bleeding or bruising
Nosebleeds
Heavy menstrual bleeding
Heartburn
Stomach pain
Nausea and vomiting
Diarrhea
Rare but serious Pradaxa side effects:
Mouth and throat ulcers
Serious bleeding events
Pradaxa also carries two boxed warnings — the FDA’s most serious medication warning. These include:
Increased risk of blood clots if you stop taking Pradaxa earlier than recommended
Spinal bleeding after certain surgical procedures
Let’s take a closer look at five Pradaxa side effects in greater detail.
1. Gastrointestinal side effects
Gastrointestinal (GI) issues are some of the most common Pradaxa side effects. They include:
Upset stomach
Stomach pain
Heartburn
Diarrhea
Nausea and vomiting
GI side effects from Pradaxa are often mild. But if they’re bothersome, taking Pradaxa with food may provide some relief. If taking Pradaxa with food doesn’t work, your prescriber may recommend a medication to relieve your symptoms. This might include medications such as an antacid, histamine-2 antagonist, or proton pump inhibitor.
If you have GI symptoms that won’t go away or become severe while taking Pradaxa, let your healthcare team know right away. This may indicate that something more serious, such as an ulcer or stomach inflammation, is present.
2. Bleeding
Pradaxa works by making it harder for your blood to clot. So it’s no surprise that one of the most common side effects is bleeding.
Cost of Pradaxa (dabigatran): Find out how much Pradaxa costs without insurance, along with ways to save on your prescription.
Blood thinner 101: Understand the difference between antiplatelet and anticoagulant medications and why one may be preferred over another.
Blood thinner interactions: Learn about medications that interact with blood thinners to help avoid unwanted issues in advance.
Your risk of bleeding with Pradaxa increases in certain situations, including if you:
Take other medications that raise your bleeding risk, such as nonsteroidal anti-inflammatory drugs (NSAIDs) or selective serotonin reuptake inhibitors (SSRIs)
Have a mechanical heart valve
Are age 75 or older
Have kidney problems
Have a history of stomach bleeds or ulcers
Minor bleeding issues can include:
Unusual bleeding from your gums
Heavier menstrual period
Frequent nosebleeds
More serious signs and symptoms of bleeding include:
Red or black stools
Coughing up blood
Vomiting blood (may look like coffee grounds)
Bruising that continues to get larger
Low hemoglobin or hematocrit levels on a blood test
Headaches, dizziness, and weakness (may indicate bleeding in the brain)
If you experience mild signs of bleeding, contact your prescriber. They can help determine if you need further care. But if you have signs or symptoms of serious bleeding, seek emergency care. If you have a life-threatening bleed, you may receive a medication called Praxbind (idarucizumab) in the hospital. This medication reverses the blood-thinning effects of Pradaxa.
3. Mouth ulcers
Ulcers are another possible side effect of Pradaxa. They may include ulcers in the mouth or esophagus (the tube that connects your mouth and stomach).
In most cases, these ulcers occur if the Pradaxa capsule opens in your mouth or becomes stuck in your throat or esophagus. To prevent this side effect, you should swallow Pradaxa capsules whole with a full glass of water. Pradaxa capsules shouldn’t be opened, broken, or chewed.
4. Blood clots
Pradaxa helps prevent blood clots. But unfortunately, clots can sometimes still happen. And there are a few situations that make blood clots more likely. These include:
If you stop Pradaxa too early. If you stop taking Pradaxa too early, you’re more likely to experience a blood clot. This can lead to life-threatening events, such as a heart attack or stroke. In fact, the medication label for Pradaxa has a boxed warning for an increased risk of blood clots when stopping Pradaxa too early. A boxed warning is the most serious warning the FDA can assign to a medication.
If you have triple-positive antiphospholipid syndrome (APS). APS is a rare autoimmune condition that causes excessive clotting. People with APS shouldn’t take Pradaxa or other DOACs. This is because you’re more likely to develop a blood clot while taking a DOAC versus warfarin if you have this medical condition.
If you have a mechanical heart valve. If you have a mechanical heart valve, taking Pradaxa can increase your risk of bleeding. But it can also increase your risk of blood clots. In studies, Pradaxa has led to clot-related events in people with mechanical heart valves. You shouldn’t take Pradaxa if you have a mechanical heart valve. Pradaxa also hasn’t been well-studied in people with bioprosthetic heart valves (tissue valves), so it’s not recommended.
If you’re prescribed Pradaxa, it’s important to take it for as long as your prescriber recommends. Always get your prescriber’s OK before stopping Pradaxa. If you experience any signs or symptoms of a blood clot while taking Pradaxa, seek emergency care. These include:
Shortness of breath
Chest pain
Pain and swelling in one or both legs
Severe headache
Trouble speaking
Numbness or weakness on one side of the body
5. Spinal problems
Certain procedures involving the spine may be risky if you take Pradaxa. Pradaxa makes it more likely to develop bleeding in your spine from these procedures. Serious consequences, such as long-term or permanent paralysis, are possible. Pradaxa’s medication label has a boxed warning for this risk.
The affected spinal procedures include:
Epidural anesthesia. This involves placing a small tube (catheter) into the lower part of your spinal cord (epidural space). Pain medication can then be injected through this catheter. It is usually needed for childbirth and procedures of the belly, legs, or feet.
Lumbar puncture. This may be needed to diagnose or treat certain medical conditions. It involves inserting a needle into the spine. Some situations where a lumbar puncture is needed include diagnosing brain infections and checking for bleeding in the brain.
To avoid this complication, your prescriber or surgeon may recommend stopping Pradaxa before your procedure. If this is recommended, you’ll want to confirm specific instructions for how to do this safely. Don’t stop taking Pradaxa without talking to your healthcare team. How long before a procedure you should stop Pradaxa depends on the procedure and your individual situation.
Frequently asked questions
Hair loss isn’t common while taking Pradaxa, but it is possible. Hair loss seems to be a possible issue while taking most blood thinner medications. But Pradaxa seems to be less likely to cause it than other options, such as warfarin or Xarelto (rivaroxaban). If you experience hair loss while taking Pradaxa, let your prescriber know. They can suggest ways to manage it or recommend an alternative blood thinner medication.
Pradaxa doesn’t require regular blood tests the way that warfarin does. So the best way to know that Pradaxa is working is the absence of blood clots. But you shouldn’t feel any different otherwise. The other thing to look out for is bleeding, which can be a sign that Pradaxa is working too well. Let your prescriber know if you’re having frequent nosebleeds or your gums often bleed while you’re brushing your teeth.
Hair loss isn’t common while taking Pradaxa, but it is possible. Hair loss seems to be a possible issue while taking most blood thinner medications. But Pradaxa seems to be less likely to cause it than other options, such as warfarin or Xarelto (rivaroxaban). If you experience hair loss while taking Pradaxa, let your prescriber know. They can suggest ways to manage it or recommend an alternative blood thinner medication.
Pradaxa doesn’t require regular blood tests the way that warfarin does. So the best way to know that Pradaxa is working is the absence of blood clots. But you shouldn’t feel any different otherwise. The other thing to look out for is bleeding, which can be a sign that Pradaxa is working too well. Let your prescriber know if you’re having frequent nosebleeds or your gums often bleed while you’re brushing your teeth.
The bottom line
Pradaxa (dabigatran) is a blood thinner that helps prevent unwanted blood clots. Common Pradaxa side effects include gastrointestinal issues such as stomach pain, heartburn, and diarrhea. Minor bleeding, such as nosebleeds or bleeding gums after brushing your teeth, is also a common side effect of Pradaxa.
More serious Pradaxa side effects include ulcers in your mouth or throat, severe bleeding, and blood clots. It can also raise the risk of complications during certain spinal procedures. Be sure to follow your prescriber’s instructions for taking Pradaxa, and don’t stop taking it on your own. If signs or symptoms of serious bleeding or blood clots occur, seek emergency care right away.
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References
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