1. Stimulants and Decongestants

Medications that contain stimulants, such as pseudoephedrine or phenylephrine, commonly found in over-the-counter cold and allergy remedies, can increase heart rate and lead to irregular heartbeats, including AFib. These stimulants can provoke AFib in individuals with a predisposition to arrhythmias or those with existing heart conditions.

2. Thyroid Medications

Medications used to treat hypothyroidism, particularly synthetic thyroid hormones like levothyroxine, can cause AFib if the dosage is too high. Excess thyroid hormone can overstimulate the heart, leading to increased heart rate and the potential for AFib, especially in older adults or those with underlying heart conditions.

3. Adrenergic Agonists

Adrenergic agonists, such as those used in some asthma medications (e.g., albuterol) and emergency treatments (e.g., epinephrine), can increase the heart's workload and trigger AFib. These medications stimulate the adrenergic receptors in the heart, which can lead to an irregular heartbeat, particularly in individuals susceptible to AFib.

4. Caffeine and Other Methylxanthines

High doses of caffeine and other methylxanthines, found in some medications for breathing disorders like theophylline, can cause cardiac arrhythmias, including AFib. The stimulating effects of these substances on the heart can lead to an irregular heartbeat in sensitive individuals.

5. Certain Antiarrhythmic Drugs

Ironically, some medications used to treat other types of arrhythmias can themselves cause AFib. Drugs like flecainide and propafenone, which are used to manage ventricular arrhythmias, can sometimes cause atrial arrhythmias as a side effect, leading to AFib in certain cases.

6. Chemotherapy Agents

Some chemotherapy drugs, particularly those classified as anthracyclines (e.g., doxorubicin), and newer targeted therapies like tyrosine kinase inhibitors, have been associated with AFib. These drugs can damage the heart muscle, leading to cardiotoxicity, which in turn can trigger AFib.

7. Corticosteroids

Corticosteroids, such as prednisone, commonly used to reduce inflammation in various conditions, have been linked to an increased risk of AFib. The exact mechanism is not entirely understood, but corticosteroids may cause electrolyte imbalances and fluid retention, both of which can contribute to the onset of AFib.

8. Alcohol Consumption and Alcohol-Based Medications

While not a medication in the traditional sense, excessive alcohol consumption is a well-known trigger for AFib. Alcohol can irritate the heart muscle, lead to electrolyte imbalances, and increase the risk of arrhythmias. Some medications containing alcohol can also have a similar effect, particularly in those already at risk for AFib.

9. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

Some studies suggest that the use of NSAIDs, such as ibuprofen and naproxen, may be linked to an increased risk of developing AFib, particularly in older adults. While the exact cause is unclear, it is believed that NSAIDs may increase blood pressure and cause fluid retention, both of which are risk factors for AFib.

Managing the Risk

If you are taking any of the medications listed above and are concerned about your risk of developing AFib, it's important to discuss these concerns with your healthcare provider. They can evaluate your overall risk, consider alternative medications if necessary, and monitor your heart health more closely.