My 19-month-old son got a stomach virus and suffered from diarrhea – without fever or pain – for a whole week. I had to stay away from work all that time. He is normally a healthy child. His doctor said I should not give him dairy products until a few days after his symptoms disappeared, but he didn’t recommend anything else, such as taking bismuth subsalicylate syrup (pink bismuth, Kalbeten or Pepto Bismol) to stop the diarrhea. Is there any problem giving this over-the-counter drug to a child this age, and are there certain kinds of food that would relieve the diarrhea? Is eating any type of dairy product bad for diarrhea? R.D., Jerusalem Veteran pharmaceutical consultant Howard Rice comments: Diarrhea can be caused by many factors – milk (lactose) intolerance; a diet too sweet for youngsters; an over oily diet, particularly rancid oils; food poisoning after consumption of insufficiently cleaned foods, or meat and fish that are not fresh (usually from bacteria, but more rarely viruses); and/or certain medications.The primary action is to identify the cause. But if this is not possible, simply give a bland diet without any components that could cause diarrhea – that is, without milk products, with very little sugar or honey (which should in any case be restricted for young children), and avoiding any food that produces too much gas.The diet should include fluid (preferably water) to compensate for the liquid loss of diarrhea, plus simple white bread and bananas (the later compensating for the loss of potassium). A little salt should also be added to the diet. The patient should then be left to pass stools for 24 hours to rid himself naturally of any toxins (infections) that may have caused the problem.Only then, if the child is not an infant (meaning he is at least three years old), should one consider giving an anti-diarrhea medication like bismuth subsalicylate syrup. This minimum recommended age was set because with children, one has to take extra care when diagnosing and prescribing so as not to miss a vital sign that may affect his health.In your case, the child is young and has no pain or temperature, yet the situation has continued for a week. Your physician wisely advised stopping milk products, since among all the other possible causes of diarrhea, this would appear to be the most obvious cause. He may be correct, but there is a possibility otherwise. If, however, you start to give anti-diarrhea medication, the diarrhea will go away (temporarily) and you will not be able to decide what the cause of the problem is. I suggest that you take the good advice given by the physician, make sure the child is drinking sufficient water and ensure that he is temporarily stopping his intake of sweet foods or fruits. Give him some simple bread, bananas, egg, fresh chicken and potatoes, and other non-gas-producing vegetables (broccoli, peas and beans, for instance, should not be eaten). The meals should be small and often, rather than large.Do not give your baby any medication unless the physician has ruled out intolerance to some foods, and then be guided by his experience with a child of 19 months.My nine-year-old son doesn’t drink enough water, even though he is very physically active and does a lot of sports. One or two times, he was dehydrated. His pediatrician gave me a color chart and said the color of his urine can indicate dehydration. Is this an accurate way to determine this?V.P., Beit Shemesh Dr. Nahum Kovalski, former deputy-director of Terem urgent care clinics and currently a medical technology consultant, replies: This is an interesting question. One of the problems with dehydration is that dehydrated children urinate less often. So it may not be possible to assess urinary color in time.I learned a simple rule – that your urine should be clear. That’s it. And if you haven’t urinated in four to six hours and have no desire to drink, then drink! This is under normal conditions without extremes of heat and when not active.For kids on the playing field (formal sports for extended periods of time), you need to push them to hydrate themselves, independently of any external signs. In the course of a wrestling match, for example, you can lose a tremendous amount of fluid. It’s the same for 15 minutes under the hot sun in full padding when playing American football. 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 9100002, fax your question to Judy Siegel-Itzkovich at (02) 538-9527, or email it to email@example.com, giving your initials, age and place of residence.