Medication may be to blame for excessive urination

Q. I urinate four to five times a night and almost every hour or more during the day. I have seen urologists and have been tested, with negative results. My body and prostate are OK. I have high blood pressure, which is under control with Norvasc. I have tried all kinds of prescription medicine: Sanctura, Toviaz, Uroxatral, Elmiron, Hyomax, imipramine, amitriptyline. I am currently taking DDAVP. Nothing has worked. I had various bladder and kidney tests. What do you suggest? I have to be careful when I travel, and I love to travel. Thank you.

A. You have undergone what appears to be extensive testing and trial of several medications. I don't know that there is much left to recommend that you haven't already done. However, I believe I may have found the culprit — Norvasc.

Between 0.1 percent and 1 percent of users may experience increased thirst, nocturia (nighttime urgency), micturition disorders (voiding abnormalities) or micturition frequency (urinating more frequently than normal but passing 2,500 milliliters or less of urine per day). Less than 0.1 percent of users may experience dysuria (painful or difficult urination) or polyuria, passing excessive (2,500 milliliters or more per day) quantities of urine.

Speak with the physician who prescribed the medication, and request a trial of another medication in a different class to control your blood pressure. If the medication is to blame, you should start to see improvement within a few days to a few weeks of stopping it.

As a matter of reference, a normal bladder can hold between 300 milliliters and 400 milliliters of urine. On average, a person urinates four to five times during the day and up to once at night, passing approximately 2,500 milliliters of urine each day. Problems arise when fluid levels are increased, causing more urination; fluid levels decrease, causing less urination and possible dehydration; the bladder muscles weaken or signals to the brain become scrambled and a host of other malfunctions can occur.

Speak with your physician and, in the meantime, limit your fluid consumption, especially before bed, to reduce the amount of urine your body is producing. Be sure to avoid dehydration, however.

Q. The only answer to my question that I find in written materials or on Internet sites is always the same: eight glasses of water per day. That across-the-board answer doesn't seem to take weight into account. A friend of mine weighs 280 pounds, and I weigh 140. Having twice the flesh that I do, shouldn't he be consuming, on average, about twice the water that I should? Is there some general equation for average daily water consumption that is weight-dependent?

A. People are too hung up on drinking a specific amount of water each day. The rule used to be eight 8-ounce glasses every day. Now there is some debate about that. My recommendation is typically to drink as much or as little as your thirst dictates; however, that is not specific enough for some people who want, it seems, a blueprint for healthy living down to the number of glasses of water to drink or the number of times a day they need to defecate. It's just plain silly. Everyone is different, so what each person requires to be healthy is different. What is normal for me is not normal for you.

With that in mind, and to the best of my knowledge, there is no weight-to-water equation. Drink if you're thirsty; don't if you're not. If that isn't good enough, try drinking enough water so that, when you urinate, it is a pale yellow color. This will ensure that you are taking in enough water to aid the kidneys in flushing toxins and waste from the body and maintaining a normal electrolyte balance. (Certain vitamins or medications can influence the color of the urine.)

Keep in mind that it is possible to drink too much water. This will cause a potentially life-threatening condition known as water intoxication. It occurs when a person drinks an excessive amount of water in a short span of time (usually over a few hours), resulting in an electrolyte imbalance that causes the water in the blood to migrate to cells. These cells then swell. If this occurs in the brain, there is no place for the cells to stretch and can result in brain damage, seizures, coma, respiratory distress and even death.

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