Eliquis, with the generic name apixaban, is a widely prescribed anticoagulant, or blood thinner [1.7.3]. It belongs to a class of drugs known as direct factor Xa inhibitors [1.7.4]. Its primary function is to reduce the blood's ability to clot, which is crucial for preventing strokes in patients with nonvalvular atrial fibrillation (an irregular heartbeat not caused by a heart valve problem) and for treating and preventing deep vein thrombosis (DVT) and pulmonary embolism (PE) [1.7.1, 1.7.2]. Despite its effectiveness, patients often have questions about its side effects, with a common one being persistent tiredness.
The Direct and Indirect Link Between Eliquis and Fatigue
While some sources list fatigue as a common side effect of Eliquis [1.2.1], it's important to note that tiredness was not officially reported as a side effect during the drug's initial clinical trials [1.9.1]. However, many patients anecdotally report a noticeable lack of energy after starting the medication [1.9.1]. The more likely explanation is that fatigue is an indirect consequence of other issues related to how Eliquis works.
The most significant indirect cause of fatigue while taking Eliquis is anemia [1.4.2].
The Role of Anemia
Eliquis works by making it harder for blood to clot, which inherently increases the risk of bleeding [1.10.1]. This can range from minor issues like easy bruising and nosebleeds to more serious internal bleeding [1.3.3]. When the body loses blood, it also loses red blood cells. A low red blood cell count is a condition called anemia [1.6.3].
Red blood cells are responsible for carrying oxygen throughout the body. When their numbers are depleted, tissues and muscles don't get enough oxygen to function efficiently, leading to common symptoms of anemia [1.4.4]:
- Fatigue and unusual tiredness or weakness [1.3.5, 1.6.2]
- Dizziness or feeling light-headed [1.4.3]
- Shortness of breath [1.4.1]
- Noticeable heartbeats (palpitations) [1.4.1]
- Paler than usual skin [1.4.1]
- Headaches [1.11.3]
Because anemia is a recognized side effect of Eliquis, occurring in up to 10% of patients, the fatigue experienced is often a direct symptom of this underlying condition [1.6.1].
Other Contributing Factors
Besides anemia, other side effects of Eliquis could contribute to a feeling of tiredness:
- Nausea: Nausea is a common side effect [1.3.4]. Persistent nausea can affect appetite and hydration, leading to general weakness and fatigue [1.2.3].
- Low Blood Pressure (Hypotension): While not a direct effect, significant bleeding can cause a drop in blood pressure, leading to dizziness, weakness, and fatigue [1.2.4, 1.3.3].
- Liver Issues: In rare instances (less than 1% of users), Eliquis can cause elevated liver enzymes or mild liver injury. Unusual fatigue can be a warning sign of liver problems [1.9.4, 1.4.5].
Comparison of Common Anticoagulants
Patients are often curious about how Eliquis compares to other blood thinners. The main difference often lies in dosing schedules and specific risk profiles.
| Feature/Side Effect | Eliquis (Apixaban) | Xarelto (Rivaroxaban) | Pradaxa (Dabigatran) | Warfarin |
|---|---|---|---|---|
| Dosing | Twice daily [1.8.2] | Once daily [1.8.2] | Twice daily | Once daily |
| Major Bleeding Risk | Lower risk than warfarin [1.8.1] | Similar risk to warfarin [1.8.1] | Lower risk than warfarin [1.8.1] | Baseline |
| Intracranial Bleeding | Lower risk than warfarin [1.8.1] | Lower risk than warfarin [1.8.1] | Lower risk than warfarin [1.8.1] | Higher risk |
| Monitoring | No routine blood monitoring required [1.7.4] | No routine blood monitoring required [1.8.2] | No routine blood monitoring needed | Frequent INR blood tests required [1.7.4] |
| Common Side Effects | Bleeding, anemia, nausea [1.3.3] | Bleeding, dizziness, fatigue [1.2.4] | Upset stomach, heartburn, bleeding | Bleeding, bruising, nausea |
Managing Fatigue and When to Contact a Doctor
If you are experiencing fatigue while taking Eliquis, it is crucial not to dismiss it. The first step is to speak with your healthcare provider [1.5.3].
What Your Doctor Might Do
- Blood Tests: Your doctor will likely order a blood test to check your red blood cell count for anemia [1.5.3].
- Symptom Review: They will ask about other symptoms to rule out serious bleeding, such as unusual bruising, black or tarry stools, or persistent headaches [1.11.3].
Lifestyle Adjustments
While waiting for medical advice, some general tips may help manage mild fatigue [1.5.1, 1.5.2]:
- Stay Hydrated: Drink plenty of water throughout the day.
- Balanced Diet: Focus on nutrient-rich foods, especially those high in iron if anemia is a concern, like leafy greens and red meat.
- Gentle Activity: Engage in light physical activity as tolerated, but avoid activities with a high risk of injury [1.10.3].
- Do Not Stop Medication: Never stop taking Eliquis without explicit instructions from your doctor. Abruptly stopping can significantly increase your risk of stroke or blood clots [1.7.3, 1.10.1].
Urgent Medical Attention
You should contact your doctor immediately or seek emergency medical help if you experience fatigue accompanied by signs of serious bleeding or other severe side effects [1.11.2, 1.11.4]:
- Bleeding that is severe, uncontrolled, or lasts a long time.
- Red, pink, or brown urine; red or black, tarry stools.
- Coughing up or vomiting blood or material that looks like coffee grounds.
- Sudden, severe headache, confusion, or vision changes.
- Numbness, tingling, or muscle weakness, especially in the legs and feet, which could indicate a spinal blood clot [1.3.4].
- Chest pain or tightness, or swelling of the face or tongue, which could be an allergic reaction [1.11.4].
Conclusion
So, is fatigue a side effect of Eliquis? While it's not a direct effect listed in initial studies, it is a real and frequently reported experience for many patients. This fatigue is most often a symptom of anemia, a known side effect caused by Eliquis's primary function of increasing bleeding risk. It's essential for anyone on Eliquis who feels unusually tired to consult their doctor to investigate the underlying cause, rule out serious bleeding, and find a safe management plan. Always prioritize communication with your healthcare provider over self-diagnosing or altering your medication regimen.
For more detailed information from the manufacturer, you can visit the official ELIQUIS® (apixaban) website.
