What Is Atrial Fibrillation (AFib)?

AFib is a condition where the heart’s upper chambers beat irregularly or too fast. This can lead to:

Fatigue

Palpitations

Shortness of breath

Increased stroke risk

AFib affects more than 6 million Americans and is more common as we age. But what many don’t realize is that some medications can trigger or worsen it—especially in those already at risk.

How Medications Can Affect Heart Rhythm

Medications can interfere with heart function in several ways:

Altering electrolyte balance (especially potassium or magnesium)

Impacting electrical signaling within heart cells

Increasing heart rate or blood pressure

Interacting with other drugs you may already be taking

While not every reaction leads to AFib, the risk grows with:

Age 60+

Pre-existing heart issues

Kidney dysfunction

Multiple prescriptions being used together

Medications Most Commonly Linked to AFib

These drugs don’t guarantee AFib—but they’ve been associated with higher risk, especially when taken without proper monitoring.

1. Decongestants and Cold Medications

Examples: Pseudoephedrine, phenylephrine (found in Sudafed and cold/flu meds)

Why they’re risky:

Stimulate the nervous system

Can increase heart rate and blood pressure

May trigger AFib episodes in sensitive individuals

Especially concerning when combined with caffeine or certain antidepressants.

2. Bronchodilators for Asthma or COPD

Examples: Albuterol, salmeterol, theophylline

These are life-saving drugs—but they:

Act on beta receptors in the lungs and the heart

Can cause palpitations or irregular heartbeats

May need dosage adjustments in older adults

Always report symptoms like fluttering or dizziness while using inhalers.

3. Thyroid Medications

Examples: Levothyroxine (Synthroid)

Thyroid hormones affect metabolism and heart rate. If overprescribed or taken in excess:

Can lead to symptoms of hyperthyroidism, including AFib

Risk increases when switching doses or brands without lab monitoring

Important to regularly check TSH and T3/T4 levels if on thyroid replacement.

4. Stimulants and ADHD Medications

Examples: Adderall, Ritalin, Vyvanse

These medications:

Raise dopamine and norepinephrine

Increase heart rate and blood pressure

May precipitate AFib in those with underlying heart conditions

More common in adults taking stimulant meds later in life for focus or fatigue.

5. Certain Chemotherapy Agents

Examples: Doxorubicin, cyclophosphamide

These powerful drugs can be toxic to heart tissue, sometimes leading to:

Irregular heartbeat

Cardiomyopathy

Long-term AFib development

Cardiac monitoring is typically part of treatment—but worth revisiting post-chemo.

6. Corticosteroids

Examples: Prednisone, methylprednisolone

Used to treat inflammation, steroids:

Can disrupt electrolyte levels

Raise blood pressure

Are associated with AFib onset, especially in high doses

Short courses may carry less risk than long-term use.

7. Certain Antidepressants and Antipsychotics

Examples: Amitriptyline, fluoxetine (Prozac), quetiapine (Seroquel)

Some of these drugs:

Prolong the QT interval (a marker for arrhythmia risk)

Interact with other cardiac or blood pressure meds

May cause palpitations or irregular beats in sensitive patients

Doctors often monitor heart rhythm when starting or adjusting psychiatric meds.

Over-the-Counter (OTC) Triggers to Watch For

You don’t need a prescription to be at risk. Some OTC products have similar effects:

Energy drinks and supplements with caffeine or guarana

Diet pills with stimulants

Nasal sprays with sympathomimetics

NSAIDs (like ibuprofen) when used in excess or with blood pressure meds

Always read labels—and ask a pharmacist before combining with other drugs.

What to Do If You’re Concerned

If you're taking any of the medications mentioned above:

✅ Don’t stop on your own—speak with your healthcare provider

✅ Ask about safer alternatives or adjusted doses

✅ Monitor for symptoms:

Skipped or rapid beats

Shortness of breath

Fatigue or confusion

✅ Request a heart rhythm check or EKG

✅ Consider a 24-hour Holter monitor if episodes are irregular or intermittent

Steps to Reduce Your AFib Risk

Even if you're taking a necessary medication, there are ways to protect your heart:

Stay hydrated

Avoid alcohol or caffeine overuse

Track blood pressure regularly

Maintain electrolyte balance with a kidney-safe diet

Inform your doctor of every medication or supplement you’re using

Many AFib episodes are triggered by multiple small factors adding up—not just one pill.