DEAR DR. ROACH: I am a 70-year-old female in excellent health, and I have a very healthy diet and fitness regimen. But I have had a persistent dry cough for 20 or so years. After seeing many doctors, it was determined to be acid reflux. I was then prescribed various acid-suppressing prescriptions such as Pepcid, Prevacid, Protonix, etc. When one didn’t seem to help, I was prescribed another, but the cough persisted.

I now see a cardiologist for heart palpitations (paroxysmal supraventricular tachycardia) and an ENT doctor for the cough. A recent endoscopy showed no damage to the esophagus. Five years ago, after a 2-hour episode of heart palpitations and a heart monitor that recorded one very brief episode of atrial fibrillation over a two-week period, I was prescribed 25 mg of metoprolol once a day at night. After a few years, I was told to cut the pill in half and take half in the morning and half at night.

The cough seems to have worsened over the past five years that I have been on metoprolol, despite being on Pepcid twice a day, Prilosec once a day, and 30 mg of amitriptyline at night. Amitriptyline is the only drug that I thought was helping the cough, but the side effects are unwelcome. When I mentioned all this to the ENT, she didn’t think that metoprolol would cause a cough.

On my own, I stopped the morning dose of metoprolol, and the cough almost stopped completely within a few days. (I took heart rate and blood pressure readings for two weeks and noted no difference.) After a month of only taking half of a metoprolol pill at night, I also stopped Prilosec. Another month has gone by, and I’m still not coughing.

I also reduced the amitriptyline to 20 mg at night, and the cough is still gone. My next step will be to wean off Pepcid and amitriptyline and see if the cough returns. Do you think that metoprolol caused the cough? — H.L.

ANSWER: You make a compelling case that metoprolol is a major cause of your cough now, but I don’t think it’s the only one. The cough certainly predated the metoprolol. I’m not sure how the diagnosis of acid reflux was made, but I suspect you have more than one reason for the cough.

The most common causes of a cough that lasts as long as yours are reflux, postnasal drip and asthma. The ENT can almost always diagnose postnasal drip with an endoscopy. However, I suspect something like asthma is the second reason for your cough.

Metoprolol is a beta blocker, and it helps people with many heart conditions including high blood pressure, arrythmias, and coronary artery disease. However, metoprolol can act on the lungs and cause constriction of the airways, which is one of the main issues in asthma.

Even people who have never had symptoms of asthma can occasionally develop symptoms with a beta blocker. But metoprolol is relatively specific for the heart, so it is less likely than other beta blockers to cause asthma symptoms, which are predominantly wheezing and cough.

I certainly recommend that you share your findings with both your cardiologist and ENT (as well as your primary doctor if you have one). The cardiologist may want you to use a different class of medicine to protect you from AFib in the future, and your ENT can opine on whether you still need antiacid treatment.

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