DEAR DR. DONOHUE: My blood test showed a low potassium level. What foods can raise it? What happens when the potassium gets low? The only medicine I take is high blood pressure medicine. – T.D.

To remedy a low potassium level, it is absolutely essential to find out why the potassium is low. Eliminating the cause eliminates the problem.

When potassium dips to low levels – lower than yours, I am sure – muscles weaken, the heart beats irregularly, and nerves cannot transmit their signals. The last effect is similar to an electric power failure.

Kidneys that are not functioning can upset potassium balance.

Adrenal gland tumors lower potassium levels. The adrenal tumor causes excessive production of a hormone that promotes loss of potassium into the urine.

Diarrhea is another cause.

The chief cause of a low potassium level is water pills (diuretics). They are the most popular drugs used when starting high blood pressure therapy. I would like to know what kind of blood pressure medicine you take. You could find the answer to the low potassium in your medicine.

I’ll give you a list of foods high in potassium, but it’s quite difficult to raise potassium levels with food alone. A potassium supplement gets the job done faster. A baked potato with skin, dried figs, bananas, salmon, oranges and orange juice, milk, kidney beans, tomatoes, chicken, cantaloupe, prunes and prune juice, watermelon and raisins contain a good supply of potassium. You can try to raise the level with foods, but if it doesn’t rise, you will have to have the doctor prescribe potassium for you.

DEAR DR. DONOHUE: One morning last month I woke with pain in my leg. I thought I must have bumped it. In less than one hour, my leg turned red, the pain increased, and I felt warm. My husband rushed me to the ER and from there into the hospital with cellulitis. They gave me 10 days of antibiotics through a vein. I never heard of cellulitis. How common is it, and how do you get it? – F.M.

Cellulitis is very common. It’s an infection of skin cells (hence the “cellulitis”) and the tissues beneath the skin. The usual villains are the strep and staph bacteria.

How they gained entrance into your skin could have been through a puncture so minute that you never noticed it. People with skin made raw by athlete’s foot are susceptible to leg cellulitis. Frequently, there is no obvious entry site for bacteria to invade the skin.

The infected skin suddenly hurts and turns red. It feels warm. You can almost watch the red border expand before your eyes. When the infection is widespread, as it was in your case, then intravenous antibiotics must be employed to obtain high antibiotic blood levels rapidly.

Most patients have total healing. A minority is left with complications, such as leg swelling. The infection can plug lymph nodes and lymph vessels. When those structures are plugged, they cannot vacuum fluid bathing tissues back into the circulation so the fluid accumulates and legs swell. I didn’t need to mention that, because the chances of it happening to you are small.

DEAR DR. DONOHUE: Please tell me: Does acne ever go away? I am 23, and I am still fighting acne. I have had it since I was 13. How long does it last? I don’t see anyone else my age with it. – J.W.

Acne reaches a pinnacle in the teen years. Once the late teen years or early 20s are reached, acne usually – but not always – goes away. By age 25, almost all are free of it. However, there are exceptions to every rule, and there are definitely exceptions to the acne-free-by-age-25 rule. Some people have to battle it into their 40s.

If you’re not already seeing a dermatologist, go to one. Be thankful for the fact that you live in an era when there are so many effective acne medicines. You should not have great trouble keeping your acne under control, and it should go away soon.

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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