I have a friend with a 12-year-old daughter who suffers from chronic enuresis (bed-wetting). She has never been dry and wets her bed practically every night. They have tried alarms and a medication called DDAVP - which had an adverse affect on her, causing her to end up in the hospital. A practitioner of the Paula method of circular muscle exercises, who is not a doctor (but says he is the son of a doctor who worked in urology) said the girl should not be awakened at night to go to the bathroom, as she has to "train herself," and he has not limited her liquid intake before going to sleep - even though parents are usually told the opposite by medical specialists who treat enuresis. The parents are desperate and don't know if there are any other doctors to see or whom else to consult. My friend said she has heard of many teenagers with enuresis who are too embarrassed to talk about it and don't know what to do. - J.D., Tel Aviv Dr. Yigal Shvil, a veteran pediatric nephrologist and former head of the unit at Hadassah University Medical Center in Jerusalem's Ein Kerem, answers: About 15 percent of children aged five suffer from enuresis, and it indeed can cause hardship and social problems. The numbers decline as they get older, but there still are some difficult cases of young people who continue to suffer from bed-wetting during their teens. There are even soldiers with this problem who are allowed to sleep at home during their period of service. Enuresis tends to run in families. There is no known gene for it, but there are hereditary influences. There may be physical or emotional problems involved. Unfortunately, there are no magic solutions that will resolve the problem in 100% of cases. There is no surgery to correct the problem. It's not like giving antibiotics for a strep throat infection and curing it. The doctor - a pediatric nephrologist or urologist - must be patient and get to know the child well. Alarms often work, as they wake the child up the moment some urine is released. Reducing liquid intake before bed and waking the child up to urinate at night often work. The drug DDAVP can be risky and if prescribed, it must be used with care, as it prevents the kidneys from producing urine for several hours. The child must not be allowed to drink at all before and after it is taken, because the concentration of urine can become dangerously high. There are clinics run by social workers, psychologists and other non-physicians that claim to have high success rates, and some of them use the Paula method. They teach exercises to control urine flow. If nothing works, the last thing to explore is whether there are any psychological problems causing enuresis; a psychologist or psychiatrist should then be consulted. My father is an 86-year-old sufferer of chronic heart disease with poor blood circulation. His condition is under control using various medications. At the same time, he suffers from rheumatoid arthritis with stiffness in the knee. I would like to know if his rheumatoid arthritis would benefit from heat or cold treatment or exercise in a hydrotherapy bath? If so, how would it affect his chronic heart disease? I understand that heart patients should not use either heat or cold - so what would the best treatment be to ease his arthritis? At the moment, he just massages his knees with various gels. - E.N., Givat Shmuel Prof. Alan Rubinow, chairman of rheumatology at Hadassah University Medical Center in Jerusalem's Ein Kerem, replies: Local heat is always better than local cold. I would recommend warm but not very hot towels so as not to burn his skin. This would not affect his heart condition. Cold is not a good idea. Hydrotherapy would not harm him but it would not give him any extra benefit beyond the hot towels. Be careful of the filled small pillows sold for heating up in the microwave, as this could cause him burns. Rx for Readers welcomes queries from readers about medical problems. Experts will answer those we find most interesting. Write Rx for Readers, The Jerusalem Post, POB 81, Jerusalem 91000, fax your question to Judy Siegel-Itzkovich at (02) 538-9527, or e-mail it to firstname.lastname@example.org, giving your initials, age and residence.