Re: Why is coca cola sometimes advised in a case of diarrhea ?

Hi - I'm not exactly certain to what you're referring, and as a physician I have never advised anyone to drink coca cola to treat diarrhea. I would recommend against it as most colas are *hypertonic* solutions, and likely to worsen a secretory diarrhea. You may be referring to the use of coke bottles in rehydration therapy of cholera and other "secretory" diarrheas when adequate medical facilities are not available.

In the case of cholera, a toxin produced by the microbe Vibrio cholerae stimulates water and chloride secretion from the intestine. Other important electrolytes such as sodium and potassium follow the chloride ions and are lost. The patients become severely dehydrated and die unless fluids and electrolytes can be adminstered. Intravenous administration of fluids is the preferred route of rehydrating patients with severe symptoms from the diarrhea. As you might imagine, many third world countries lack wide-spread facilities to give IV fluids. Fortunately, the intestine has a "back door" of sorts that can allow water and electrolytes taken orally to be absorbed. The intestinal transport of the sugar glucose is coupled with the transport of sodium. Water, potassium and other electrolytes passively follow the sodium and glucose. By drinking a solution of glucose and salts, patients have a chance of absorbing sufficient electrolytes to get them through their illness.

As for the reference to coca-cola, I suspect it has to with the bottle and not the cola itself.

For cholera, the WHO created a recipe for oral rehydration salts that could easily be prepared and administered. The salts could be distributed to areas experiencing an epidemic. However, how could the solution be prepared with the correct amount of water if no measuring devices were available? As it turned out, the glass coca-cola bottle proved the most widely available "measuring cup" found from location to location. The guidelines for rehydrating the salts are often given in, "number of coca cola bottles of water," to add to the salt packets.

Hope this helps..

Lynn Bry, MD/PhD
Brigham & Women's Hospital
Boston, MA 02115