DEAR DR. DONOHUE: I am a physician at a major university and am interested in untreated head injuries. I am trying to amass information on concussions, so I designed a Web site. It has 17 multiple-choice questions for those who have suffered a head injury. They are easily answered, and participants are not required to identify themselves. The Web site is www.ihitmyhead.com. I would appreciate it if readers who have had a head injury and have not seen a doctor would use this site. – J.B., M.D.

ANSWER: I am happy to assist you in your study, Doctor.

Most people associate a concussion with loss of consciousness. Such is not the case.

A grade I concussion produces transient, short-lived confusion. Other symptoms can be dizziness, headache and nausea. If all symptoms resolve in 15 minutes, a player can return to the game if an examining doctor permits it.

A grade II concussion includes the above symptoms along with loss of memory about how the injury occurred. Symptoms last longer than 15 minutes. A player with this kind of concussion should not return to play and should be given a thorough medical examination.

A grade III concussion is one that produces unconsciousness. Regardless of how long the player is unresponsive, that player ought to be transferred to an emergency department for rigorous testing and perhaps a brain scan.

These remarks are not directed solely at football players. Older people often suffer a concussion when they fall. They fall because age robs a person of the sense of balance.

Readers, please help the doctor. The information he’s gathering is important information for young and old. It won’t be a waste of your time to comply.

DEAR DR. DONOHUE: A friend told me that riding a bike can affect the prostate gland. I bike-ride for four miles every day. My doctor said he has no information on bike-riding affecting the prostate gland. My friend is not a doctor, but he knows a lot. – Anon.

ANSWER: The firmness of a bike’s seat and the forward bend bikers assume put lots of pressure on all the structures located in the seat area, prostate gland included.

Gland irritation is one possible consequence.

Nerve irritation is another. The area, including the penis, can become numb. Without a rest, impotence can occur because of pressure damage to the nerves supplying the penis.

These problems resolve almost all the time if a biker takes a vacation from riding.

Women bikers too can come down with problems. Their short urethra – the tube that drains urine from the bladder – can become infected and transmit the infection to the bladder.

There are bicycle seats designed to circumvent such problems. One such seat has no nose – the elongated, narrow front of a bike seat. Another seat consists of two unjoined pads. That leaves a space between the two pads so no pressure is put on the sensitive area.

Don’t buy a new bike seat without trying it for yourself. I angered a reader by suggesting a brand name of a bike seat. He bought the seat, and it did not do him one bit of good.

DEAR DR. DONOHUE: When people speak of “steroids” for building muscles, do they mean prednisone? I know it’s a steroid, and I take it. It is definitely not building me any muscles. What is the meaning of “steroids”? – C.J.

ANSWER: Steroids cover a large number of artificial and natural hormones. The steroids used to build muscles are male hormones also called anabolic (muscle-building) hormones. Testosterone, Halotestin, Durabolin, and Winstrol are some brand names for this kind of steroid.

Cortisone is an entirely different sort of steroid. Our adrenal glands make it for us. It is made artificially to suppress inflammation. Prednisone is one of the cortisone drugs. There are many others. They do not build muscles. Used for protracted periods and in high doses they can shrink muscles.

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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