DEAR DR. DONOHUE: I was plagued with a persistent, hacking cough that was embarrassing and annoying. I was treated with antibiotics on two different occasions. They didn’t work. I had a chest X-ray that showed nothing. I was exasperated, but I suddenly remembered how my mother couldn’t sleep at night because of a cough, and how it turned out to be caused by acid reflux. I asked my doctor if I might have acid reflux. He said let’s try some medicine. To end the tale, I was able to stop coughing through medicine and diet. Why don’t doctors consider acid reflux as a cause of a persistent cough? – J.W.

ANSWER: A persistent cough is one that lasts longer than three weeks. One of its major causes is postnasal drip, the irritating trickle of mucus from the nose or sinuses into the throat. Equally important as a cause is asthma, and it is often a variety of asthma that does not present with typical asthma wheezing symptoms. A third player in the persistent cough struggle is a combination of postnasal drip and asthma. These two conditions, either alone or in combination, account for a sizeable number of chronic coughs.

Not to be eclipsed as a major player is acid reflux, also called GERD (gastroesophageal reflux disease) – or, in common speech, heartburn. The backup of stomach juices and acid into the esophagus and eventually into the larynx (voice box) and airways can provoke paroxysms of coughing. Medicines that turn off or lower the production of stomach acid can miraculously turn off cough due to acid reflux. Your experience speaks for itself.

Although the above are common causes for a cough that lingers, they are not the only causes. Serious conditions – cancer being the prime example – have to be considered. Medicines are another cause of coughing, and ACE inhibitor medicines, which are used for blood pressure control, among other things, are high on the list of medicines that induce coughing.

DEAR DR. DONOHUE: About two years ago I started having canker sores. They can flare up so bad that it’s hard to eat or brush my teeth. How do I get relief? I have tried many over-the-counter meds, but nothing works. – R.R.

ANSWER: Although the cause of canker sores has yet to be completely resolved, preliminary evidence suggests that the immune system has a hand in their occurrence.

Keep a list of foods you eat to see if there is any relationship between a particular food and an outbreak. Some find that nuts and seafood provoke outbreaks of canker sores. Those are not the only two implicated foods.

Many prescription medicines can ease the pain of an outbreak and often shorten its duration. Lidocaine Viscous is a thick liquid that can be painted on the sores. Lidocaine deadens pain; it’s a relative of novocaine. Aphthasol paste, when spread on the sores with a finger, can also relieve pain and accelerate healing.

A suspension of the antibiotic tetracycline, swished in the mouth, has been used for many years as a treatment. Cortisone drugs, when incorporated into substances that keep them from dissolving in saliva, are also effective in soothing canker sore irritation and pain. Kenalog in Orabase is one such product.

Want to try a homemade remedy? Mix equal parts of milk of magnesia with Benadryl Allergy liquid (on the shelves of drugstores) and swish some in the mouth for one minute. Don’t swallow. Spit it out. Repeat four to six times a day. Let me know the results.

DEAR DR. DONOHUE: I have a question about the reader who had only one kidney. You said we could live OK with just one kidney and even a partial kidney. At what point does a patient need dialysis if he has only one kidney that is only partially functioning? I am curious because I have a relative with only one kidney, and it is failing. – E.B.

ANSWER: When kidney function falls to 20 percent or less of normal, then body chemistry is gravely compromised, and toxic products accumulate in the blood. At that point, dialysis is mandatory — or kidney transplant.

DEAR DR. DONOHUE: I found the enclosed ad in a magazine. Can you tell me more? – M.N.

ANSWER: (The ad says that aspirin can trigger an asthma attack in 20 percent of asthmatic adults.) Some asthma patients are very sensitive to aspirin, and it can cause them to have a severe asthma attack. The actual percentage of asthmatics who are so affected is more often quoted to be in the range of 5 percent.

Asthmatics who are aspirin-sensitive often have difficult-to-manage asthma. Along with that, they frequently have nasal polyps. The reason why this is so is obscure, but it is a fact.

DEAR DR. DONOHUE: I read your explanation of cellulitis, and I have a couple of questions not covered in your answer.

Can cellulitis be caused by trauma such as a fall or injury? What determines the treatment? It seems that the majority of cases are in the legs. Since the symptoms are similar, is there any link with gout? – H.F.

ANSWER: Cellulitis is an infection of skin cells and the tissues immediately beneath the skin. It is a bacterial infection, usually with the strep or staph germ.

The germs have to gain entrance to the skin. They can do so by an insignificant scratch or by more severe trauma such as a fall or injury.

Treatment is always with antibiotics, ones that are effective against staph and strep germs.

The legs are frequently the sites of cellulitis, but they are not the only sites. Legs are subject to more bangs and cuts than any other body location.

Cellulitis and gout are not related in any way.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475.

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