Brief Answer:
stool culture and perhaps antibiotic treatment has to be considered

Detailed Answer:
Hello,

this is probably a gastroenteritis. The presence of fever (particularly if higher than 38 degrees of Celsius or 100.4 F) is against using imodium for the diarrhea because it could make things worse. Regarding the cause of this condition, a gastroenteritis could be due to either a preformed toxin in the food you ate or a pathogen (virus or bacterium).

If you've come into contact with other patients (particularly kids) then the viral etiology could be more likely. If you've used antibiotics recently then it could be antibiotic associated diarrhea. Recent travel outside your country may be associated to travellers diarrhea.

In any case, since it's lasting for more than 2 days, a stool microscopic examination and stool culture would be very useful in determining the cause and deciding on treatment. The stool culture results will be obtained after a couple of days, so the microscopic examination is the first test which will provide more clues as to the cause.

Signs of inflammation in the microscopic examination along with fever may drive your doctor to prescribe antibiotics. The doctor should evaluate your clinical status to decide on further management. A dehydrated patient who vomits a lot, is prone to serious complications and should be aggressively hydrated even if it requires hospitalization. If the patient can receive an adequate amount of fluid, in order to produce more than 30-40mL or urine per hour then management as an outpatient would be feasible.

So in conclusion, I would advise against using imodium. Remember to drink enough fluids and visit your doctor for clinical examination and tests (stool culture and microscopic examination). Further treatment with antibiotics might be required as described above.

I hope you find my comments helpful!
You can contact me again, if you'd like any clarification or further information.

Kind Regards!

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