DEAR DR. DONOHUE: I play fast-pitch softball for my company’s baseball team. A couple of days ago, I got hit on the tip of my right ring finger with a line drive. Since then, the tip of the finger bends downward. I can’t straighten it. It hurts a bit, but not enough that it has sent me to a doctor.

Will it eventually straighten out? Is there something I should be doing for it? My friends tell me that it will go back to normal in a few days and that I should just wait things out. – M.J.

ANSWER: Your friends are wrong. I hope you haven’t waited to see this answer in the paper before you’ve been to a doctor. If you haven’t had a doctor examine the finger, do so – today or tomorrow.

Your finger injury is a common baseball casualty – a jammed finger. It happens just as you describe. The ball hits the tip of a finger and the force of the impact pulls a tendon away from its attachment. The fingertip bends downward, and you cannot return it to its normal position.

The standard treatment for this injury is splinting the finger. The splint stays on for six to eight weeks. At that time, the splint can be removed during the day, but it is put back on at night for another two to four weeks.

Sometimes surgical reattachment of the tendon is required.

You really must see a doctor. This injury doesn’t heal on its own, and there’s nothing you can do at home to help it.

DEAR DR. DONOHUE: I swim in a gym’s pool anywhere from half an hour to 45 minutes three times a week. There is so much chlorine in the water that it makes me wonder what damage chlorine can do to the body. The last three times I swam, I felt really nauseated and all around yucky within two to three hours of getting home.

I know chlorine can be dangerous and that medicine skin patches work by penetrating the skin. Our bodies must absorb chlorine, so what is it doing to our bodies?

I am working to lose 70 pounds but am concerned about the chlorine. – R.C.

ANSWER: Chlorine has been used as a disinfectant for swimming pools for more than a hundred years. It has been proven to be a reliable way to keep swimming pool water free from bacteria and viruses without harming swimmers. You would not want to swim in a pool that doesn’t have chlorine.

The people who provide pool maintenance must follow standards for chlorinating the water. They have to make sure the chlorine concentration is in a safe and effective range and that the pool water’s acidity is acceptable.

Chlorinated water can dry the skin and hair and make hair brittle. A swimming cap protects the hair. Taking a soapy shower immediately after getting out of the water keeps the skin from drying out.

If swimming pool water is too acidic, it can cause tooth erosion.

The “chlorine” odor people talk about isn’t really chlorine. It’s chloramines, byproducts that arise when pollutants in the water react with the chlorine in the water.

If the water is properly maintained and the chlorine level is checked as it should be, no bad things happen to swimmers.

DEAR DR. DONOHUE: My 3-year-old granddaughter has been doing pull-ups ever since she could stand up. Now she hangs from the baby’s crib and does pull-ups and then lets herself down. Her cousin has been told to cut down on exercising because she is showing evidence of muscle destruction. Do I need to worry about my granddaughter? – A.F.

ANSWER: It sounds like a safe exercise to me. I wondered if it could cause “nursemaid’s elbow” a condition that occurs in children younger than 5 who are lifted up by their hands with outstretched arms. I asked a doctor with much more experience in these matters than I have, and he said it wouldn’t cause damage. She won’t hurt her arms or her muscles.

DEAR DR. DONOHUE: After taking a low-dose aspirin daily for 10 years, I developed a stomach ulcer, for which I am now being treated. I was put on aspirin because there was a possibility I might have had a small stroke. Obviously, the doctor treating me for the ulcer stopped my aspirin. Is there any way to get the benefits of aspirin, like a skin patch, without causing damage to one’s stomach? – R.C.

ANSWER: Aspirin doesn’t do a number on the stomach when it’s in the stomach. The effect of aspirin on the stomach takes place after aspirin gets into the blood. It interferes with the production of the stomach’s protective coating.

There are other medicines that can prevent blood clots in arteries, as aspirin does, in order to forestall heart attacks and strokes. One is Plavix. It can irritate the stomach too, but not to the degree aspirin can. Persantine is another drug with antiplatelet activity and, therefore, is of some use in heart attack and stroke prevention. Ask your doctor if either of them might be the right medicine for you.

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 www.rbmamall.com