DEAR DR. DONOHUE: While my doctor was listening to my heart during my annual physical examination, I saw him wince. He listened for quite some time. Then he looked up and told me I have atrial fibrillation. He put me on medicine, and I have to go back to see him. He said he has a few other things up his sleeve.

What are those things? I don’t feel any different than I ever have. — L.H.

ANSWER: The atria are the two upper heart chambers. The right atrium receives blood coming from veins, and that blood contains little oxygen. The left atrium receives blood from the lungs that has its oxygen content restored. In atrial fibrillation, these two chambers are writhing at a rapid and erratic rate. A flurry of electrical activity coming from the atrium causes it. The two lower pumping heart chambers follow the atria’s lead and begin contracting rapidly and erratically, but not as fast as the atria. Causes of atrial fibrillation are many. Heart-valve disease, partially blocked heart arteries and high blood pressure are some of its causes. An overactive thyroid gland is another cause. And it also happens in hearts without any discernible abnormality.

The consequences of atrial fibrillation are serious. It decreases the volume of blood pumped with each heartbeat and can throw a person into heart failure. It produces episodes of lightheadedness and shortness of breath.

The most devastating consequence of atrial fibrillation is a stroke. Blood stagnates in the fibrillating atria. Stagnant blood forms clots. Those clots can be carried in the circulation to brain arteries and plug them. The result is a stroke.

If atrial fibrillation is recent, a slight shock to the heart sometimes can restore a normal beat. For others, medicines revert fibrillation to normal rhythm. If medicines don’t establish a regular heartbeat, they slow the heart so that it pumps out a sufficient blood supply. Radio waves, delivered by a catheter to the atria’s interior, create roadblocks that stop the errant, irregular electrical impulses causing this rhythm — another treatment. Blood-thinning medicines are needed to prevent clot formation and the possibility of stroke.

The booklet on abnormal heartbeats deals with atrial fibrillation and its many treatments. To obtain a copy, write: Dr. Donohue — No. 107, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Allow four weeks for delivery.

DEAR DR. DONOHUE: I recently stubbed my great toe. My mother isn’t sure how long it will be sore. What do you think? — S.S.

ANSWER: Ever bang your elbow or the tip of your finger against a wall? How long did it take you to get over those injuries? Probably a week or two, right? That’s how long it takes to get over a stubbed toe. Stubbing the toe breaks blood vessels, and the toe swells and hurts. It gets better on its own. If you soak the toe in warm water for 15 minutes, three or four times a day, it heals faster.

DEAR DR. DONOHUE: I smoke marijuana to fall asleep at night. What are the long-term physical and mental effects of smoking this? — B.

ANSWER: Frequent and heavy marijuana use raises the risk of serious gum disease. It can impair memory and decrease learning aptitude. It appears to have the same effect on lungs that cigarettes have — emphysema and chronic bronchitis. A relatively light use doesn’t pose such dangers. It is, however, an illegal drug, and you can still suffer consequences on that front.

DEAR DR. DONOHUE: In response to the person who had hives and was not getting any better from using Atarax, I had the same problem. I tried every medicine imaginable. Nothing worked for me. Finally a doctor suggested I try Allegra. Reluctantly, I did. The hives are gone. If I forget to take it, they come back. I feel free and wonderful. Thank God for Allegra. — D.K.

ANSWER: Thanks for the tip. I will pass it on so others can try it. I hope they meet with the same success you did.

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. Readers may also order health newsletters from

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