If you’ve recently been diagnosed with atrial fibrillation (AFib), you may wonder if you need to avoid certain over-the-counter or prescription medications to protect your heart health. Some commonly used drugs, like cold medicine, painkillers, and antibiotics, may worsen AFib symptoms. They could also cause dangerous interactions with the drugs you may be taking to treat AFib.

This article will cover some of the potential drug interactions you should be aware of. Always consult your health care provider or pharmacist about medication safety and your specific health needs. Make sure your doctor knows about any drugs you may be taking, whether prescription or over the counter.

1. Decongestants

Over-the counter decongestants are medications that clear your sinuses when you’re stuffed up or have a cold. While decongestants can be useful for cold symptom relief, they may not be ideal to use if you have atrial fibrillation. Many decongestants use pseudoephedrine and phenylephrine as ingredients. These agents can cause your heart rate to increase, which can be troublesome for people with AFib whose heart rate may already be higher than normal.

Safer options for people with AFib are Coricidin HBP cough and cold medicines, which were made specifically for people with heart disease or high blood pressure. They may not be as effective as pseudoephedrine-based decongestants, but they can help with symptoms like itching and a runny nose. Be aware that most Coricidin products contain an antihistamine, which can make you sleepy.

2. Over-the-Counter Painkillers

Over-the-counter painkillers can pose a risk to individuals with AFib. These can include nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, naproxen, or aspirin. These can interact with other medications people with AFib tend to take.

Individuals with AFib are usually prescribed anticoagulants, also known as blood thinners. They help lower the chance of having a blood clot. Because these medications thin the blood, combining them with anti-inflammatory medications like ibuprofen, naproxen, and aspirin can increase your risk of bleeding. NSAIDs should be used with caution if you’re taking an anticoagulant like warfarin.

A safer option for over-the-counter pain relief would be acetaminophen (Tylenol), as long as you don’t have any liver dysfunction. Check with your doctor to see which pain relievers might be right for you.

3. Stimulants

Stimulants are medicines that speed up your heart rate and make you feel alert. They do this by activating certain hormones and brain chemicals. This leads to vasoconstriction, or narrowing of the blood vessels. These drugs can be risky for people with atrial fibrillation because they make the heart beat faster and raise your blood pressure. Both can increase your risk of blood clots and stroke.

Doctors prescribe stimulants for conditions like attention-deficit/hyperactivity disorder, binge eating disorder, and narcolepsy. You might know some of these medications as methylphenidate (Ritalin), dextroamphetamine-amphetamine (Adderall), or lisdexamfetamine (Vyvanse). People with atrial fibrillation should use stimulants carefully — and only with a doctor’s supervision — due to their effect on the heartbeat and blood pressure.

Nonprescription stimulants like caffeine and nicotine may also affect the body’s heart rate and blood pressure. These could also pose risks for people with AFib. Lastly, illegal drugs such as cocaine and methamphetamine have similar effects on the heart and are also unsafe.

4. Antimicrobials

Some antimicrobial drugs may cause problems for individuals with atrial fibrillation. Antimicrobials, including antibiotics and antifungals, kill bacteria or fungi that cause infections in the body. Many studies have found that individuals taking warfarin have a higher risk of severe bleeding when they take certain antibiotic or antifungal medications, due to the interactions with how the body processes warfarin or other medications commonly used for AFib.

If you are prescribed antibiotics or antifungals for an infection, be sure to let your doctor know if you’re also taking warfarin.

5. Some Asthma Medications

If you have atrial fibrillation, it’s important to be cautious with certain prescription asthma medications. Asthma drugs like bronchodilators and oral steroids can be risky for individuals with AFib. Bronchodilators are medications that widen the lungs to allow more air in. Oral steroids are used to reduce inflammation in the airways. Bronchodilators can cause similar effects as decongestants, such as widening of blood vessels and increased heart rate and contractions. Both have been shown to pose a risk if you have AFib.

If you have AFib and you’re being treated for asthma, be sure any doctor you see is aware of both of your health conditions. They can help you find a safe treatment plan to manage your symptoms.

6. Certain Thyroid Medications

High levels of thyroid hormones in the blood can lead to heart palpitations — fluttering sensations in the chest — and arrhythmias. Certain medications for thyroid disorders can raise the amount of thyroid hormones in the blood but pose a danger for individuals with AFib. When taking a medication like levothyroxine for underactive thyroid, it’s important that thyroid hormone levels are closely monitored. Be sure to attend all follow-up appointments with your doctor.

Talk to Your Doctor

While this list covers many of the drugs that should be avoided with AFib, it doesn’t include all of them. Ultimately, every individual with AFib has a different set of health circumstances that will make a drug more or less risky for them. With medical expertise and an understanding of your unique medical history, your heart doctor or cardiologist can guide you on what drugs to avoid and what treatment options are safe for you.

Talk With Others Who Understand

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Are you or your loved one living with atrial fibrillation? Has your doctor told you to avoid certain drugs? Share your experience in the comments below, or start a conversation by posting on your Activities page.