Have you ever taken a medication and noticed your heart racing or fluttering unexpectedly? While side effects like dizziness or nausea are often expected, one lesser-known risk linked to certain medications is atrial fibrillation—a type of irregular heartbeat that can increase your risk of stroke or heart failure.
Atrial fibrillation
Atrial fibrillation, or AFib, affects millions of Americans each year. What’s surprising is that some of the most commonly prescribed drugs could be quietly triggering it. If you or a loved one is on long-term medication, it’s worth learning which ones may be affecting your heart rhythm—especially if you've experienced palpitations or fatigue lately.
Here are five medications that have been associated with atrial fibrillation, and what you should know about each one:
1. Albuterol (and other beta-agonist inhalers)
Used widely to treat asthma and chronic obstructive pulmonary disease (COPD), albuterol works by relaxing airway muscles. But it also stimulates the heart, sometimes excessively. For people with underlying heart conditions—or even those who are otherwise healthy—this can provoke AFib episodes, especially at high doses or with frequent use.
2. Over-the-Counter Cold Medications (Decongestants)
Think twice before grabbing that cold relief tablet. Common decongestants like pseudoephedrine and phenylephrine can spike blood pressure and overstimulate your cardiovascular system. While these are marketed as harmless, they’ve been linked to irregular heart rhythms, including atrial fibrillation, particularly in older adults.
3. Corticosteroids (Prednisone, Methylprednisolone)
Used to reduce inflammation for conditions like arthritis, lupus, and allergic reactions, corticosteroids can indirectly impact your heart rhythm. They may increase blood pressure and disturb electrolyte balance, both of which are triggers for AFib. Even short-term use has been associated with new-onset arrhythmias in some studies.
4. Certain Chemotherapy Drugs
Drugs like doxorubicin and cyclophosphamide are potent cancer fighters—but they can also take a toll on the heart. These medications may cause structural or electrical changes in the heart muscle, creating a pathway for atrial fibrillation to develop, especially in older cancer patients or those with pre-existing heart issues.
5. Thyroid Medications (Levothyroxine)
While not everyone will react this way, too high a dose of thyroid hormone can push the heart into overdrive. Patients with hyperthyroidism—or those being treated aggressively with levothyroxine—have shown higher rates of AFib, especially if their hormone levels become imbalanced.
What Should You Do If You're Concerned?
If you’re taking any of these medications and notice symptoms like a racing heart, shortness of breath, or unexplained fatigue, don’t panic—but don’t ignore it either. AFib can be managed, especially when caught early.
Never stop a prescribed medication without talking to your doctor. Instead, have a conversation about your risks. There may be alternatives or dosage adjustments that can help protect your heart without sacrificing treatment.