Unwelcome guests Pt.2

steve.jpgAfter reading my PBlog “Unwelcome guests” my dear friend Dr. Dave Mozley made some insightful points to me about some other aspects in the treatment of travelers diarrhea that he thought would be helpful to others in the context of traveling to developing countries. Dave and I have made many difficult trips together and he’s taught me a great deal about a variety of topics and the handling of all manner of trying situations while abroad. Dave has been traveling all over the world for years and he’s been a member of the medical community for over twenty years. He’s currently working in research for a major pharmaceutical company in the United States.

I think you’ll find the real beauty of “Moz’s” approach to travelers diarrhea is it not only lays out the physiologic mechanisms of the affliction but also gives some very pragmatic and logical solutions for curing this all too common woe abroad, and some really viable treatment options so you won’t be “Shit out of luck” if you didn’t pack Immodium or can’t get your hands on any Cipro, or worst of all contract one of the new anti biotic resistant strains of bacteria that are becoming more and more common throughout the world.

By Dr. Dave Mozley M.D.>

Palliative Treatments of Dysentery

Purpose: As Napoleon observed, diarrhea has defeated more armies than all of history’s great generals combined. The specific aim of this prescription is to review some of the steps that stricken travelers should take to get back into combat as quickly as possible.

Background: Most travelers’ diarrhea syndromes are caused by pre-formed endotoxins. The “loudest” of these proteins tend to be resistant to degradation by stomach acid, bile salts, and the alkaline environment in the small bowel. No medication will destroy them. They must be eliminated. Once they bind receptors in the gut, they produce secretory diarrheas. Simply put, the gut tries to defend itself from invasion by what it assumes are live organisms by flushing them out with water. This is the key point from which all rational treatments follow logically.

Methods: the treatment of vomiting. The water for the gut’s fire hydrant comes from the extra-cellular fluid. Water in the extra-cellular fluid comes from the blood. Water in the blood comes from direct absorption across the gastric mucosa (and the distal colon). So point one is to put as much fluid as possible into the stomach. It does not matter how much you are vomiting. It’s virtually impossible to throw up more water than you put down. If you don’t get lots of water in, then the water going out will leave you dehydrated. Dehydration is pathological for a variety of reasons, not the least of which include the shunting of water from the muscles other internal organs to the gut, leaving you weak. Your brain suffers, and in its attempt to cope with the situation, tries to put you down on your back. Water is good medicine and exactly what you need for a variety of reasons. It’s relatively easy to regurgitate. Barfing up undiluted gastric juice is harsh on your esophagus, and bad for your teeth. Adding a lot of water to your stomach is a good way to wash out any remaining food as well as the offending agents in them. You should engorge yourself with water until you are regurgitating only clear, non-bitter tasting fluid. Some physicians like to prescribe clear sodas, like 7 Up. They taste good, and the bicarbonates in them are great buffers for gastric acids. The sugar in them can mitigate the feelings of lassitude. Colas are not favored because of their caffeine content. Caffeine tends to sustain and prolong the signal transduction caused by the binding of the endotoxins, so it can be thought of as relatively contraindicated. Dentists, of course, are appalled by the prescription of any sweet soda waters. Tooth decay is greatly promoted by stomach acid, and they would argue that any kind of sugar water in the oropharynx adds insult to injury. Apple juice is a reasonable compromise that is endorsed by many pediatricians. Orange juice is contraindicated because it is very acidic. Teas are worse because the solute loads in them cause the kidneys to loose more water excreting the solutes than the amount of fluids in the brews that are absorbed by the gut. Complex solutions like Gatorade or the electrolyte packets you add to water are unquestionably beneficial for the subchronic stages of major dysenteries, but free water is all that’s indicated during the acute stages of almost any diarrhea, and all that most travelers ever need. And, it’s often all that’s available when these syndromes wake you up either 6 or 12 hours after ingesting the problem.

Methods: treating diarrhea. Back in 1983, the family practitioners in rural North Carolina taught me that the psyllium they usually prescribed for constipation was the treatment of choice for these kinds of diarrheas. Their rational was so clear and compelling that the white haired physicians in Center City Philadelphia didn’t take more than a minute to convince that this was also useful on the urban wards when I interned in 1984. Products like Metamucil and its competitors work because they cannot be digested or absorbed by the gut. They are hydroscopic, meaning they absorb water. But, they hold the water they absorb within the lumen of the gut, where it forms a slurry, that is, a sort of mud. That’s nice for people who suffer from the constipation caused by hard, compact, water deficient feces. The same phenomenology applies to diarrhea. The psyilium mixes with the secreted water and forms a mud. Even nicer, whatever is dissolved in the water moves into the mud with it. Most endotoxins are water soluble proteins that are easily trapped within the mud. Live bugs are stupid, and get trapped in there too. As a consequence, the endotoxins are not able to bind the receptors on the brush border of the gastrointestinal (GI) tract. In this way, the offending agents are removed from the compartment that causes harm before they are eliminated from the intra-luminal space. When they are eventually eliminated from the terminal end of the GI tract, evacuating a slurry is gentler on the rectum than passing water. It’s also less messy, which might explain why some of the Philadelphia nurses were as enthusiastic as this kind of treatment as some of the physicians and patients. (And that might be an important point; anecdotal as it might be, patients almost invariably agree these maneuvers are helpful.)

Methods: re-feeding. The time to start eating again is before you feel like it. Practically speaking, with either a 6 or 12 hour lag time between ingestion of the offending agents and the start of their repudiation, most bouts of dysentery start during the night. As a consequence, you should plan on eating breakfast. Pediatricians usually recommend a BRAT diet: bananas, rice, applesauce, and toast. A multivitamin (with lots of water) is generally all that’s necessary to replace depleted electrolytes, such as the potassium that’s lost with vomiting. Gatorade and packets of electrolytes are nice if available, but unnecessary. Whatever you eat, select foods that are relatively easy to digest (and regurgitate in case you’re not quite done). Cereals are perfect. Avoid most fruits; they taste good, but are generally hard to digest. Nuts are difficult to digest under ordinary circumstances, and not recommended except as an unavoidable component of granola bars and trail mixes. A lot of thoughtful people recommend local yogurt for a variety of reasons. Whether or not the big bacillus in yogurt can really reach the colon and help establish a new and improved equilibrium is not really clear, but it tastes good and is easy to digest.

Drugs: Medications are available to terminate any and all of the symptoms of dysentery. But, none are recommended for travelers’ diarrhea, and most are contra-indicated. Food gets trapped in the stomach due to a healthy reflex that sends the pyloric sphincter at the gastroduedenal junction into spasm. You want to eliminate this food, and since there’s only one way out, puking is a physiological, i.e., healthy, response to the insult. Similarly, you want the offending agents that already made it into the small intestine out of there, and since the only way to get them out is through the back door, you want to avoid the anti-diarrheals. Save these for 12 hours after the last episode of vomiting if you need to be on the move. Otherwise, a second dose of Metamucil will serve you better.

Summary: Plan on coming down with a case or two of dysentery. Carry individual packets of psyllium fiber (about 0.4 oz or 12 grams per packet). Push fluids hard once stricken whether you feel like it or not, and keep hydrating yourself as much as possible between episodes of vomiting. Avoid medications for symptomatic relief until you’re sure the acute episode has passed. Carry multi-vitamins, as they’re always good for you and extremely beneficial in situations like these. Anti-bacterials like Cipro are not the first line of treatment for classic episodes that start 6-to12 hours after ingesting nasties. In most cases, you should wait at least 12 to 18 hours to see if hostilities end on their own before starting a chemical war.

  9 comments for “Unwelcome guests Pt.2

  1. fansy
    January 10, 2007 at 9:09 am

    One thing to keep in mind: For those places a traveler may go where s/he does not have good access to clean water (either because of microbes or chemical pollutants), drinking as much water as possible may become problematic. If someone were to down a good load of the tap water in Central Asia thinking it would help them out in a bout of the shits, they might end up in the hospital. Of course the traveler must always apply his or her common sense to the situation at hand, but in some places access to good water is just scarce.

    I wonder, if a situation called on the rationing of water, what would be the optimal solution. As much as possible at first? Saving it until after the acute episode? I remember my father always used to tell me, taking on the tone of veteran a Native American brave, that the silly white man would ration out his water while crossing the desert instead of drinking as much as possible up front. My father is not Native American and so I always doubted this piece of advice, but it seems pertinent to the topic; and in turn I diarrheaed it right out of the dark recesses of my brain for all readers to enjoy and marvel at.


  2. Stiv
    January 10, 2007 at 10:25 am

    Thanks for your input Fansy. Interesting and entertaining as always.

    I’ll try and scare up Moz for some more input.


  3. January 10, 2007 at 11:24 pm

    I was under the impression that water shouldn’t be rationed? Drink when you get thirsty? Could be wrong there.

  4. fansy
    January 11, 2007 at 8:52 am

    Rob, that is the advice I have always heard; but it seems to be a general rule of water intake when on the trail or on the move. I’m willing to bet though, that in the event of an acute episode, if good water is scarce, you should wait as long as possible on the intake since you won’t always have the option of gulping more down after you continually puke it up.

    As his advice is very water intensive, the small benefit you get from ingesting water whilst puking will be negatively offset, I believe, by the lack of good water to drink following the episode – at which time you really can hold it down and are at your most dehydrated state.

  5. Mozley
    January 21, 2007 at 7:09 pm

    Thank you all for your interest in my companion piece to the article on antibiotics by Mr. Strommer. You’re quite right that my advice assumed the source of free-water would be reasonably safe, and just as you noted, not all fluids qualify. A point-by-point response follows to some of the other issues you raised.

    Drinking biologically contaminated water. It’s fair for you to note that most people don’t prefer to suffer from a major illness caused by the treatment of a minor illness. The probability of contracting cholera from water along stretches of the Congo is almost 100%, and it’s often fatal. (Until Dr. John Snow discovered the association between sewage and cholera in 1855, the same could once be said for stretches of the Thames.) Cholera is an interesting case in favor of your point because its latency is short. That is, the time lag between drinking infested water and getting sick is often only 1-to-3 days. Most other infectious agents in water have 7-to-14 day lag times, and the amebiasis that I once contracted in Irian Jaya had a latency of almost a month. Perhaps it means that in extreme scenarios, such as those in the middle of the night in places where one is forced to drink tap-water from unreliable sources because there are no reasonable alternatives available, there is often enough time to start prophylactic antibiotics after the acute dysentery has passed. This principle probably holds for most bacterial and parasitic infections in otherwise healthy adults who will not die from ingesting common GI viruses like little children often do.

    Drinking chemically contaminated water. Similar considerations hold, although the lag-times for most diseases caused by chemicals in drinking water are quite long, many being measured in years or decades. Chemically induced diseases usually require chronic exposure to relatively high doses of the chemotoxin, and as a consequence, very large volumes of contaminated water. In other words, the relationships between dose and risk seem much more straightforward for chemicals than biologicals. In many cases, where it’s only the chemical quality of the tap water that is uncertain, it’s probably best to drink it liberally during a bout of acute dysentery. But, as you and others alluded to, sensitivity to the local environment and a modicum of discretion seem indicated. After all, it apparently required only one cup of polonium-210 contaminated tea to kill a man in London last year.

    Drinking water with minerals. Most bottled waters are relatively expensive for good reasons related to their safety. Caution, however, is indicated in this context when it comes to the concentration of magnesium (Mg++). Magnesium is an effective laxative. Its concentration in most bottled waters is too low to cause a problem, but I once saw it induce a diarrheal syndrome resembling dysentery in two American women in Morocco who constantly drank locally bottled mineral water as a matter of nervous habit. If there is doubt about the integrity of bottled water, one can select “water with gas”—that is, carbonated water. The extra bicarbonate is actually good for your health when you’re vomiting a lot, but the key point here is that tap water or river water cannot be fraudulently sold in a used bottle as “water with gas”.

    Remember, dehydration kills, and kills quickly. It’s ultimately the cause of death in old men who have heart attacks while shoveling snow, as well as young sailors who fall into the North Atlantic for much more than about 20 minutes, even if they’re pulled out alive. It took only one day’s march to dehydrate the Crusader’s army from Jerusalem in 1187. Saladin (Salah al-Din) then massacred them while they struggled to reach the water’s edge in a weakened state.

    In summary, fluid is the first line of treatment in cases of acute traveler’s dysentery. It is prudent to secure a source of safe water wherever you go. Put a liter of a fluid you trust near your bed every night. It’s not likely to go to waste even if you remain perfectly healthy. It’s not always wise to try sailing across a sea or trekking across a desert without secure provisions for water.

    Incidentally, the relationships between hydration and performance are beyond the scope of this conversation. I will say only that if you’re a racehorse trying to win the Kentucky Derby in a 120 second burst of speed, dehydration could be advantageous. That’s why it’s illegal to give racehorses furosemide (Lasix). But, travelers who are out on the road for a long time seem well advised to act more like turtles, and keep themselves hydrated.

  6. Fansy
    February 5, 2007 at 5:26 pm

    As someone who always has more questions than answers, my response will follow in form:

    My main question/comment concerning biological contamination is grounded in the situational consideration. Suppose a traveler was hit with the symptomatic diarrhea while in the hinterlands (trekking, out-of-the-way sight-seeing, etc). Perhaps a trip to a place with proper treatment is at least 3-4 days out (either because of distance or because local transport only runs as such). Let’s also assume that water must be rationed, or perhaps its nearest source cannot be trusted (in effect creating a rationing situation of available, trusted water). My question seeks to understand the optimal choice: risking a second biological contamination by using possibly contaminated water (out in the wild, so to speak) or ingesting only that water which can be insured safe? It seems there are many factors that could affect the balance here, and I would venture to guess that your advice would still be to drink what water is available and relatively safe – I guess my question boils down to this: at what time, in what situation, is it a good idea to ration or hold off? Is Cholera the most biologically significant risk (if lag times over 5 days or so were considered “safe”)? This is not really meant to be a negation of anything that was said, but just my brain firing off possibly problematic scenarios.

    >In summary, fluid is the first line of treatment in cases of acute traveler’s dysentery. It is prudent to >secure a source of safe water wherever you go. Put a liter of a fluid you trust near your bed every >night. It’s not likely to go to waste even if you remain perfectly healthy.

    This is great advice. I commented to Steve, this page (especially with your response here) has provided me extremely useful information on the subject. I was an EMT a while ago (for a few months in college) but unfortunately most of its specialized knowledge does not translate well to travel and life in developing countries. We discussed dysentery but only as much as it affected the young and the old, and of course the small scope of interventions in which an EMT-B is allowed to practice with regards to the illness (we can’t even start an IV). I never came across a case of it in my short time working (and thank god have not been afflicted with it yet while traveling).
    Always a pleasure to see learning combined with a willingness to spill the beans on topics of expertise. Appreciate it much.


  7. February 6, 2007 at 12:10 pm

    Dr. Mozley is at a conference but said you can expect a response to your latest questions in a few days.

    Also I was asked about the link for “Unwelcome guests Pt.1” that can be found here:



  8. Neeta Cheeta
    February 6, 2007 at 5:10 pm

    Is psyilium safe for kids? …had to ask!

  9. Mozley
    February 20, 2007 at 12:39 am

    Thanks for helping me order my thoughts on the matter. Extrapolating to extreme scenarios has helped me better elucidate some of the principles from which complex judgments should follow logically, even when there is uncertainty about the integrity of the fluid one uses to treat dehydration.

    The first fundamental principle to consider is that one acute bout of dysentery enhances resistance to another. From this it follows that victims of acute dysentery should drink without worry; the primary concern is dehydration. Some of the reasons follow from simple observations of how a body responds to the perception of a biological toxin or foreign organism.

    Mechanical: The pyloric sphincter that regulates the movement of substances between the stomach and the small intestine contracts. In fact, it goes into a sustained spasm. The contents above the sphincter are regurgitated, and anything in the lumen of the bowel below the sphincter is purged. A lot of fluid is secreted into the bowel to help wash things out. The net result is that any foreign proteins or organisms tend to get flushed out of the tube. Several other biological reflexes come on line that are also well modeled as partially mechanical in nature, even though they are chemically mediated. The net result is that they limit the ability of foreign organisms to invade the lining of the GI tract.

    Immunological: Once a threat is perceived by one part of the system, the entire system tends to activate. Chemical messengers are secreted into the local area as well as the whole circulatory system. These chemical messengers tend to activate all of the immune cells in the body, as well as the local area. Most immune cells can be modeled as sleepy and lazy under ordinary circumstances, but they tend to become ferocious in response to chemical alarms sent out by other cells. Once activated by a messenger from another cell, these cells send out more alarm messengers, which amplifies the response. An invading organism has its best chance of getting past your immune defenses while these cells are quiescent; it’s a lot harder for the same bug, or any new bug, to get through once the system is activated.

    The net result of all of these defenses is dehydration: you vomit fluids, you secrete fluids into the gut that are evacuated as diarrhea, and your circulation increases in speed as well as volume per unit of tissue. The best treatment is to drink as much fluid as you can tolerate. Some of the pure water you drink will be absorbed across the gastric mucosa, but none of the particles in the water will be. Some water and some of the smallest particles will get past the pyloric sphincter, but the bowel will only absorb the free water. It will purge most of the water and any particles in it. While I don’t have hard data in hand from a prospective clinical trial to prove it, it follows that an acute bout of dysentery will tend to make its victim more resistant, not less resistant, to attack by another biological toxin or organism in the fluid you drink to treat the acute dehydration.

    It’s not clear that there are any circumstances where this principle wouldn’t hold true for the treatment of acute dysentery in otherwise healthy adults. Of course, people with certain types of special disabilities or chronic illnesses might be forced to contemplate more complex scenarios, but it’s probably better for most people to drink water that is of uncertain purity than to risk the consequences of dehydration. Again, dehydration can kill, and kill quickly, while most of the causes of acute dysentery are much more limited in their ability to cause morbidity and mortality.

    Again, as we’ve all acknowledged, some discretion and an appreciation of the local environment is indicated. One wouldn’t be well advised to drink turpentine, tequila, or tea that had been made by the KGB. But, my old professors still seem correct: drink as much as you can even if you are certain to vomit part of every mouthful.

    Incidentally, psyillium is very benign, even in neonates and toddlers. It’s only contraindicated in astronauts and people who have undergone certain types of bowel resections.

    Very best.


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