For this reason it is useful to understand how one could diagnose and treat one's self if medical help is not readily available. From what we have learned above, it is clear that the main decisions to be made is whether the illness is due to food poisoning, bacteria, or protozoa. There can also be fever. But the illness rarely lasts more than 6-12 hours, and by the time you can think about leaving your room to seek help, you generally find that all of the symptoms are disappearing rapidly. No further therapy is required except to rest and re-hydrate yourself as necessary.
Bacterial diarrhea is defined as the sudden onset of relatively uncomfortable diarrhea.
Of course there will always be a time when you did not have diarrhea and a time that it began, but bacterial diarrhea can have a more memorable way of starting than a protozoal diarrhea. The onset of uncomfortable cramping and the uncontrollable urge to defecate comes rapidly, and most patients remember the exact time that their illness began. Fever, nausea, and vomiting can also accompany bacterial diarrhea, but they don't have to be present to make the diagnosis. Occasionally, bacterial diarrhea can be preceded by a day of fever and feeling uncomfortable, with no specific intestinal symptoms. Then the next day the diarrhea begins suddenly.