DEAR DR. ROACH: Would you please explain water intoxication, when a person consumes too much water? I teach swimming to young children in Florida. I tell their parents to watch closely for symptoms of water intoxication when they submerge under water. Please explain, so I can advise them. -- C.C.

ANSWER: Water intoxication is when the balance of water and salt in the body is disturbed, and there is more free water than there should be. The blood sodium level will be too low. This is uncommon in healthy adults, since the ability of the kidneys to regulate salt and water balance is impressive.

However, in small children, excess water intake can lead to low sodium levels, and this can be life-threatening. Shortly after swallowing excess water, symptoms may include irritability, lethargy and disorientation. In more severe cases, vomiting and seizures may occur.

Although this is a rare event, it is wise to know the symptoms and be ready to bring the child to medical attention if these symptoms occur after a swim lesson.

DEAR DR. ROACH: Despite an ample supply of lubricant, intercourse for my wife is painful, and all activity has ceased. She is 70. -- T.F.

ANSWER: There are many possible causes for painful intercourse, and these include infection, interstitial cystitis and endometriosis. Only a careful history and physical exam by a gynecologist or other provider trained in women’s issues can sort it out. However, the most common cause in post-menopausal women is atrophic vaginitis, which can be effectively treated with vaginal estrogen creams. These are safe and have few side effects for most women. Have your wife start by speaking frankly with her family doctor.

DEAR DR. ROACH: If the instructions for a medication say to take with food, does it matter whether the medication is taken before, during or after a meal? I am taking Excedrin on an empty stomach in the morning and afternoon, about half an hour before eating. Can this be damaging to the stomach? -- D.

ANSWER: Taking medication with food is done for different reasons. In the case of Excedrin, or any aspirin-containing medication, having food in the stomach when the medicine is taken can prevent damage to the lining of the stomach. As long as the medication is taken immediately before eating, that is OK, too. I wouldn’t recommend waiting a half-hour.

       Other medications have different food requirements. For example, Fosamax is not absorbed with food, so it needs to be taken on an empty stomach.

       DEAR DR. ROACH: I’ve been diagnosed with stage IV, inoperable, incurable pancreatic cancer, which has spread to my ovaries and peritoneum. I am currently undergoing chemotherapy. I’ve been told that this disease is terminal. What exactly does that mean? What is the (longest) time a person can live with this type of cancer, and why do they call it “terminal”? Recently, the PET scan showed “shrinkage” (although I still look nine months pregnant) -- does this mean I am close to being cancer-free? I’m confused. -- T.F.M.

       ANSWER: I am so sorry to hear about your diagnosis.

       Physicians are not very good at predicting what will happen, even when people have extensive cancer. Pancreatic cancer is almost never cured, and when it is, it’s because it was found very early, usually when looking for something else. Once it has spread throughout the body, barring a miracle, the cancer eventually will prevail.

       How long that takes can vary drastically. Six months is the average time of survival for metastatic disease. Very few people will live more than two years. The fact that your cancer seemed to shrink with treatment is a good sign, but to be called cancer-free, there would have to be no cancer found by any test.

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       Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Health newsletters may be ordered from www.rbmamall.com.

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