Medical Edge Newspaper Column

Reducing Nighttime Trips to the Toilet

March 19, 2007
Dear Mayo Clinic:
I'm 74 years old. My urologist says my PSA is 1.04 and the digital exam shows no problem, but I still wake up three or four times a night to urinate. Is there something I can do about this that is not too invasive?

Answer:
When a man reports a frequent need to urinate at night, conventional wisdom says the "usual suspects" involve the urinary tract -- the kidneys, bladder, or prostate gland.

But the source may be non-urological, and it makes sense to look at these causes first, especially when the man's prostate exam is normal (as yours appears to be) and the problem occurs only at night. An obstructing prostate or an overactive bladder, after all, would most often show symptoms all the time.

A major possibility is sleep disturbance: Once you've been roused at night for other reasons, it's natural to sense the status of the bladder and react accordingly. Thus realizing the need to go may be an effect rather than a cause of your awakening.

Sleep disturbances can manifest themselves in several ways; I commonly look for obstructive sleep apnea. It occurs when muscle tissues at the back of the throat relax during sleep and narrow or close your airway, which impairs breathing. The brain then senses the situation and wakes you. If you live with someone else and he or she observes that you snore loudly or often stop breathing during the night, you may be suffering from sleep apnea.

Another leading cause of needing to urinate at night is peripheral edema, a buildup of fluid around the feet, ankles, and legs prompted by a wide variety of possible reasons, including too much standing during the day or heart, liver, or blood-vessel diseases. During the night, we lie flat and the excess fluid that has settled in our lower limbs during the day is redistributed. Much of it winds up in the kidneys, and this newly mobilized load on the bladder soon prompts awakening.

It's also possible that some arthritic pain, or another cause of discomfort -- such as restless leg syndrome -- could be awakening you. And there are many medical conditions -- as well as some of the drugs used to treat them -- that can cause frequent urination, especially at night. For instance, if you have hypertension and are taking a diuretic for it at bedtime, the resulting urine generation will likely prompt nighttime lavatory visits. Taking the drug at a different time should help the problem.

Other behavioral modifications include restricting fluid intake after your evening meal; avoiding caffeinated beverages and dietary irritants in the evening; and adopting the practice of "double voiding" -- urinating a second time, a few minutes after going the first time, to better empty the bladder.

If you experience urinary frequency not only at nighttime but also during the day, and possibly a sense of urgency, a slow or hesitant stream, or the need to strain in order to urinate, the problem likely does involve the urinary tract itself. One of the most common such conditions -- prostate gland enlargement, also called benign prostatic hyperplasia (BPH) -- typically becomes a greater nuisance as men get older.

I often prescribe an alpha blocker, such as tamsulosin (Flomax) or alfuzosin (Uroxatral), to treat BPH. It relaxes the muscles that, affected by the enlarged prostate, have constricted the tube that carries urine out of the bladder. Another option is a 5-alpha-reductase inhibitor, such as finasteride (Proscar) or dutasteride (Avodart), to directly shrink the prostate. The two approaches can also be used together.

In urological and non-urological causes of sleep disturbance alike, the idea is to treat the problem at its source through the best available medical and behavioral means. But among men your age it is normal to get up once or twice during the night to urinate. So while it makes sense to try to avoid taking even more trips, a goal of zero is probably unrealistic.

-- Lance A. Mynderse, M.D., Urology, Mayo Clinic, Rochester, Minn.