The Red Brick Times

We who are survivors of everything that has happened since birth keep discovering new and startling things. Patience. Forbearance. Endurance. Medical procedures. The chorus of exhortations for early diagnosis of treatable and preventable demise seems adequate for those who will listen, and will not sway those who will be deaf. So I stopped saying "What a good idea. I really have to do that. Someday." I blundered into the scary realization that Yes, I AM old enough, and Yes, it DOES mean me. So I followed Katie Couric and had a colonoscopy. Not bad. No discomfort. No national television. So go and do it yourself. Just another form of peering into one's navel, so to speak.

What IS under individual control is what happens before your special day. A pain in the tuckus it can be. And inconvenient. But the good doctor inquisitor must have a clear field of vision to follow her/his calling, so the patient supine needs to empty his/her er-mind of all obstructions to progress.

The prescribed chemical of choice to accomplish this seems to be PEG 3350. My sister had some abominable surgery last year and had a bottle of the powder used for prep. "What is it?" I asked her. "Let me get it and read it to you," she said. "Poly, poly- ethel - lean gly..." "Polyethylene Glycol?" I interrupted, in disbelief. "That's automotive antifreeze!" "That's what it says," she affirmed. "Polyethylene Glycol 3350 NF powder for oral solution. Rx only. 255 grams."

It turns out that polyethylene glycol is a long-chain polymer that bonds to water and prevents it from being absorbed by the intestines, thereby instigating a flow-through action that acts to flush the pipes clear. Different companies add different stuff. The one my sister had was a generic from Breckenridge Pharmaceutical, Inc. that cross-references to the Miralax Powder brand name. It was straight PEG 3350 with no additives noted on the label. The cap was the measure of 17g of powder to be mixed with 240ml (8 ounces) of water and downed, one dose every 6 hours for 24 hours (4 doses).

The one prescribed to me was a generic from Kremers Urban, Llc. that cross-references to GoLytely brand by Braintree Labs. It is a large 4 liter plastic bottle with the powder in the bottom. You are to add water to the 4L line, shake it up, and refrigerate. It contains electrolytes (Sodium Bicarbonate, Sodium Chloride, Potassium Chloride). I got the little flavor powder package to add to it that the pharmacy offered (I chose pineapple, but there is cherry, orange and lemon-lime). One is to slam 8 ounces every 10 minutes until the first half (2 liters) is gone. Then wait 2-6 hours and repeat for the last 2 liters.

Now for the consumer report:
I did the chemistry thing, decanting and weighing the powders, comparing and calculating the concentrations in milli-moles per liter, making up solutions to match. There are two philosophies to this thing: fast or slow. In either case, no solids for 24 hours prior to the event. Nothing containing any kind of red dye or coloring. That leaves clear chicken or turkey broth, yellow jello, yellow popsicles, clear sports drinks and water. What was never said to me in advance, but was made clear just before the exam, was that there was to be nothing taken by mouth after bedtime of the night before. No water, nothing. Watch out for dehydration or low blood sugar effects. I had a 7:30AM appointment, showed up by 7AM and waited for the doctor to arrive at 9AM. He had some problem with getting his car out of the garage ("Dammit, Jim! I'm a doctor, not an auto mechanic!").

The PEG without additives tastes slightly like a new plastic cup, but a rinse and swallow with plain water after an 8 oz shooter took care of that. Odd, but not objectionable. I did the half and half guzzle in 2-hour doses with a couple of hours between at work. After the first hour, don't plan any long conference calls or meetings. The toughest moment was when I walked quickly to the rest room and every stall was already occupied. I had no idea that colonoscopies were getting so popular.

later at home, I mixed the PEG with electrolytes. It was pretty icky. Drink it cold, drink it fast and don't think about it. The electrolytes gave it a not quite metallic, but not quite liquid feel. Instead of the clear quenching feel of water, it felt like the water was hiding behind something round and smooth and not satisfying. The water was obviously bound up by the PEG and the ionic electrolyte solutions were modifying the taste and mouth feel. The pineapple flavoring added some artificial sweetener, and something almost, but not quite, entirely unlike pineapple. Since I had done the other stuff at work that day, I only mixed half of this stuff and ingested 2 L, as directed, within two hours. It works very effectively. Think fire hose.

So don't just take the prescription and follow directions blindly like a trusting puppy. Closely question the issuer (mine was a nurse practitioner) and make the preparation fit your schedule and preference. So don't worry when someone accuses you of having your head up your rear. Its a good thing. And don't be anal retentive.

PS: Polyethylene Glycol works in radiators of cars because it locks up the water molecules with the polymer chain, preventing it from boiling away at 212 degrees F. It must get much hotter to evaporate, and much colder to crystallize. That lets it work as a liquid in a much wider temperature range to carry heat away from the engine and to the air flowing through the radiator.
Posted 8:40 AM by Andy (1) comments

       Comments:

Change to my posting - the automotive version of the chemical is poisonous ethylene glycol, which has (2) carbons in the backbone with hydrogen and hydroxyl radicals attached (CH2OHCH2OH). The POLY in polyethylene glycol means that there are many repetitions of that basic unit. The longer the chain, the heaver the molecule. Up to molecular weight 700 (PEG 700), it is a viscous liquid. Above molecular weight 1000 (PEG 1000) it is a waxlike solid. PEG 3350 is what is used for colonoscopy prep. This molecule is too big to be absorbed. All ethylene glycols bond to water.

# posted by  Andy : February 27, 2010 12:01 PM
 
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