DEAR DR. DONOHUE: I have arthritis, and I take Motrin for it. It works well for me. An arthritis specialist put me on it. My primary care doctor told me to take an aspirin a day because I am at high risk for a heart attack.

A friend tells me not to take both. Why? I don’t think my doctors know that I am taking both Motrin and aspirin. – P.T.

ANSWER: People who have had a heart attack or who are at high risk for having one are often told to take a daily aspirin. When clots form in heart arteries, they block blood flow to heart muscle.

When blood flow is cut off, the heart muscle served by the clogged arteries dies. That’s a heart attack.

Aspirin prevents clots from forming in arteries. It stops blood platelets from sticking to each other. When a blood vessel is cut or broken, platelets sticking to each other form a plug that seals the broken vessel. That’s good. When platelets stick to each other when there is no bleeding, the clot serves as a dam blocking blood flow. That’s bad.

Motrin (ibuprofen) is a member of the drug family called nonsteroidal anti-inflammatory drugs – NSAIDs. NSAIDs relieve both the pain and inflammation in arthritic joints. Aleve, Indocin, Orudis, Toradol, Naprosyn, Daypro, Voltaren, Clinoril, Celebrex and Vioxx are other commonly used NSAIDs.

Motrin blocks aspirin’s effectiveness in preventing clots from forming in arteries.

First, tell both your doctors your dilemma. There are ways of working around it. One is to choose another NSAID that does not interfere with aspirin. The other is to take aspirin first thing in the morning and let two hours pass before taking Motrin. Motrin will not interfere with aspirin when aspirin is taken first. Timing is everything.

DEAR DR. DONOHUE: What is secondary hypertension? I am in my 30s, and on three different visits to the doctor my blood pressure was high.

The doctor says I might have secondary hypertension and wants me to undergo special tests. What does it mean to have secondary hypertension? – W.T.

ANSWER: So everyone has it straight, hypertension is high blood pressure.

Ninety percent of people with hypertension have essential hypertension. That means a cause for their high blood pressure cannot be found.

Secondary hypertension, while rare, is a mixed blessing. The rise in pressure does all the bad things that essential hypertension does – enlarges the heart, attacks arteries, damages kidneys, etc. However, a cause for the elevated pressure is found.

An example is a tumor of the adrenal glands that produces hormones that elevate blood pressure. Removal of the tumor restores normal blood pressure. The rise in pressure was “secondary” to the tumor. There are other examples of causes for secondary hypertension, but let’s let it go at this.

The onset of high blood pressure at a young age raises the suspicion of secondary hypertension. Your doctor is serving you well by looking for potential secondary causes.

DEAR DR. DONOHUE: My left leg became red, hot and tender. The doctor says it is cellulitis. He has put me on antibiotics and has told me that if the leg doesn’t get better soon, I will have to go into the hospital for intravenous antibiotics. Why wait? Wouldn’t it be better to hospitalize me now? Exactly what is cellulitis? – R.J.

ANSWER: Cellulitis is an infection of skin cells and the tissues under the skin. The staph or strep germ is the usual cause.

A break in the skin, so small that you never paid attention to it, can provide germs with the opportunity to invade the skin and multiply rapidly.

As you say, the skin turns red, becomes hot and hurts.

Usually oral antibiotics taken at home can cure cellulitis. Only a few people ever need hospitalization for it.

If you can stay out of the hospital, so much the better for you. Hospitals are not fun places.

Only if the infection quickly spreads and your temperature shoots up would you need hospital-based treatment.

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.