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People's Pharmacy: Colonoscopy prep can be challenging

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Q. My question is about the prep for colonoscopy. My husband has had two; I have had one. It seemed to me that, although the prep was unpleasant for both of us, it was worse for me. Consequently, when it came time for my second colonoscopy, I opted for Cologuard instead, with my doctor’s agreement.

I weigh 120 pounds, and my husband weighs 210 pounds. Are any allowances made for such size differences when the prep solution is prescribed?

A. Periodic colonoscopies are an excellent way to detect colon cancer or, preferably, polyps even before they go rogue and turn into cancer. Since the polyps are removed during the procedure, they should not have a chance to cause further trouble.

You are correct that the bowel prep prescribed before a colonoscopy usually comes in a standard amount of powdered polyethylene glycol (PEG, an osmotic laxative), often with electrolytes, to be dissolved in 4 liters of water.

The traditional instructions do allow for some personalization of dose. Patients are told to drink a cup every 10 minutes until the watery stool is completely clear. If you reached that point sooner than your husband, you could stop earlier.

Newer recommendations call for a “split-dose” approach. People are told to drink half the solution in 10- to 15-minute intervals starting in the late afternoon or early evening before the procedure. The second half is consumed in increments about four to six hours before the colonoscopy. Don’t give up on colon cancer screening; it can be a lifesaver.

Q. Some years ago, my aunt was doing poorly, so I took my mother to see her. Because I’m a doctor, I was asked to review the meds. She had six over-the-counter and 25 prescribed drugs with various dangerous or negating interactions. She was barely able to get out of bed.

Her primary care doc knew all the meds were a problem but would not change them because specialists had prescribed them.

The medication taper was tricky and required ER visits, but my aunt got off most of the benzos, narcotics and sleeping pills, as well as most of the other multi-specialty drug mess. She regained her alertness and lived well for over five years. Drug interactions are underappreciated, especially as a problem for older people.

A. We couldn’t have said this better! It’s far too easy for older people to accumulate drug prescriptions that may not work well together. Someone should monitor for medication incompatibility and lobby for deprescribing when appropriate.

Write to Joe and Teresa Graedon in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email them via their website:


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