Travelers’ Diarrhea (Montezuma’s revenge in Mexico)
I am starting with a digression to make an important, subtle, and
interesting point.
Clindamycin is an old antibiotic, seldom used anymore because of early
experience with its major side effect, pseudomembranous enterocolitis, which
results in very persistent diarrhea.
Now that we know the mechanism of this syndrome, it is called
Clostridium difficile infection.
Clindamycin, more than other antibiotics, inhibits the portion of normal
bowel flora that prevents overgrowth of C. difficile previously present in
small numbers or available from the environment to colonize us—its spores are
very long lived. Lesson: if your doctor
gives you an antibiotic to take in case of travelers’ diarrhea, wait a few days
after symptoms before you take it (unless you have a very important business
appointment). You will probably get
better before you need the antibiotic, and you will dodge any threat of C.
difficile infection. Its like not
killing barnyard cats to avoid an infestation of rats. C. difficile now occurs mostly in
chronically ill people who need multiple courses of antibiotics (seldom
clindamycin).
Here
is the second instructive digression.
Cholera is a disease with such severe diarrhea that fatal dehydration
can occur in an hour or so. We never
saw a case of cholera in two years teaching in Afghanistan, but we learned to
teach its treatment because we saw frequent cases of what we called “the cholera
syndrome” caused by an enormous dose of ordinary staphylococcus food poisoning
resulting in the fulminating life-threatening diarrhea, just like cholera
itself for the first few hours. The
treatment is to replace the lost fluid as fast as it is lost, either
intravenously or orally. Trade names
for the oral packets include Rehydralyte, Resol, Ricalyte (Gatorade is too
dilute).
The
diarrhea of food poisoning is a very good example of why you shouldn’t take
powerful antidiarrheal medications such as Lomotil and Imodium at the first sign
of diarrhea (Kaopectate and Pepto-Bismol are OK) ---you might interfere with
nature trying to push the toxin out as promptly as she can. A smaller point, other causes of travelers’
diarrhea such as salmonella may be prolonged by agents such as Lomotil. In other words, save them for the
denouement—the winding down after the climax.
If you
travel to areas remote from medical attention or if you want to be
self-sufficient, ask your physician for a prescription for rifaximin (Xifaxan)
to be taken in case of life-threatening diarrhea with dehydration. One tablet (200 mg) three times a day for
three days would give you a good chance of prompt cure. For a “belt and suspenders” program: also
ask for a prescription for Cipro 500mg two times a day for 7 to 14 days in case
of failure with rifaximin. For more self-sufficiency remember that rifaximin is
not absorbed from the intestinal tract and therefore is not effective for
infections elsewhere in the body.
Summary: when you get travelers’ diarrhea, try to put up with it for a
day or so. If it isn’t getting better
by then, get a stool culture if you can (maybe it came on after you got
home). By the time the culture is reported,
you will know whether you are a candidate for antibiotic treatment, and more
importantly you will get the most appropriate antibiotic for your bug.
To
avoid trouble in problem parts of the world; 1) practice brushing your teeth
out of a canteen for a week or so at home; 2) avoid raw food; 3) watch out for
salads especially in ritzy digs with cloth napkins and table cloths (a false
sense of security). 4) in some countries bottled water is simply filled from
the tap—nose around (asking questions may or may not suffice); 5) ice cubes are
a subtle threat—you cannot treat them with Halozone and taking them out of your
drink is too late.
My
credential: I survived two years in Afghanistan with only one attack of
dysentery—I saw the host use ordinary water to wipe the knife he was using to cut watermelon. We had been three weeks without fresh food
and there was something of a political problem—the latter perhaps why some of
our counterpart Afghan physicians only boiled their drinking water when they
were sick already.
John A. Frantz, MD, Green County Health Committee, September 27, 2005