DEAR DR. DONOHUE: Is phlebitis the same as blood clots? My daughter has phlebitis. She was given aspirin and told to keep her leg elevated. After the birth of my fourth child, I had phlebitis. I was treated in the hospital for it and was put on blood thinners. Has the thinking on phlebitis changed? – V.M.

ANSWER: Phlebitis (flea-BITE-us) is vein inflammation. In most cases, a clot has formed in the vein, and the proper term is actually “thrombophlebitis” – the “thrombo” indicating “clot.” And most of the time, this happens in a leg vein.

The seriousness of phlebitis in a leg vein centers on its location. If the involved vein is near the surface – under the skin – the condition is superficial phlebitis, and it causes redness, pain and swelling, but it’s not usually a danger to health or life.

If the involved vein is one buried deep in muscles – a deep vein – then the problem takes on much more importance. Pieces of a deep-vein clot can break loose and be swept in the circulation to the lungs. A broken-off piece of a clot is called an embolus.

The embolus can cut off blood supply to a part of the lung. Then you have a pulmonary infarct, the lung equivalent of a heart attack. A large pulmonary infarct can be fatal.

Blood thinners are given to people with deep-vein phlebitis to prevent growth of the clot and the possibility that growth will give rise to an embolus. Deep-vein clots are treated with great respect and almost always in the hospital.

Your experience after delivery is not all that unusual. That’s a time when clot formation is apt to happen. Other situations where clots form easily and where the threat of their consequences has to be considered are heart failure, cancer, when on bed rest or taking birth-control pills and post-operatively. Your daughter must have superficial phlebitis.

DEAR DR. DONOHUE: I just had my dog vaccinated, and it got me thinking about rabies. How many cases of it happen every year? Just what is the sickness like? I wonder how necessary these pet vaccinations are. If there aren’t many cases, do we need to continue the vaccination programs? – H.L.

ANSWER: The value of pet-vaccination programs for rabies is proved by the small number of yearly rabies deaths in the United States – three. And those cases are ones that have been transmitted by wild animals.

Rabies is an awful illness. After a bite from a rabid animal, signs of the illness appear between one and three months later and sometimes much longer afterward.

The earliest symptoms are nondescript – sore throat, headache and a slight fever. After a few days to a full week, the florid rabies signs emerge. Throat muscles develop spasms that make swallowing impossible. Offering a rabies patient water sends him or her into violent throat spasms; hydrophobia – fear of water – is a classic rabies sign.

Patients are hyperactive, and they produce large volumes of saliva. They drift into and out of consciousness and finally slip into a coma. Only one known rabies patient has survived after signs and symptoms developed. Today, animals most likely to transmit this illness are bats, raccoons, skunks and foxes. Early treatment, before any signs and symptoms appear, prevents the illness from developing.

DEAR DR. DONOHUE: I chew sugarless gum. It has sorbitol, a sugar alcohol. I have been told to cut back on my sugar intake. How can this be marketed as “sugarless”? – M.J.

ANSWER: For some reason, sugar alcohols have become a big topic for my readers.

These products aren’t sugars, although they’re sweet and are used as sugar substitutes. Furthermore, they aren’t alcohol – they don’t make you drunk.

Foods that contain sugar alcohols are allowed to be marketed as sugar-free.

However, if you’re strictly watching your carbohydrates, multiply the number of grams of sugar alcohol in a food by 2.5 to give you the amount of carbohydrate calories in the food.

A few sticks of gum won’t put you over the limit for such calories.

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