Oral or IV fluids
Sometimes antidiarrheal agents and/or antiemetics
Supportive care including rehydration with fluids and electrolytes is the mainstay of treatment and is all that is needed for most adults. Oral glucose-electrolyte solutions, broth, or bouillon may prevent dehydration or treat mild dehydration. Children may become dehydrated more quickly and should be given an appropriate rehydration solution (several are available commercially—see Oral Rehydration Oral Rehydration Oral fluid therapy is effective, safe, convenient, and inexpensive compared with IV therapy. Oral fluid therapy is recommended by the American Academy of Pediatrics and the World Health Organization... read more ). An antiemetic (eg, ondansetron) may be given if vomiting makes oral rehydration difficult.
Isotonic IV fluids such as Ringer’s lactate and normal saline solution should be given when there is severe dehydration, shock, or altered mental status and ileus or failure of oral rehydration therapy (see also the Infectious Diseases Society of America's [IDSA] 2017 clinical practice guidelines for the diagnosis and management of infectious diarrhea). In severe dehydration, IV rehydration should be continued until pulse, perfusion, and mental status normalize.
Antidiarrheal agents should not be given to children < 18 years of age with acute diarrhea (see the IDSA guidelines). Antidiarrheals can be considered in adult patients with watery diarrhea (as shown by heme-negative stool), especially during an outbreak, suggesting a viral cause is likely. However, antidiarrheals may cause deterioration of patients with Clostridioides difficile or E. coli O157:H7 infection and thus should not be given to any patients in whom the cause of diarrhea has not been identified and in whom these disorders may be suspected (ie, based on recent antibiotic use, bloody diarrhea, heme-positive stool, or diarrhea with fever).