Brief Answer:
if acute, infection is the most common cause

Detailed Answer:
HI, thanks for using healthcare magic

Infection of the GI tract is the most common cause of an acute (recent, short term) diarrhea.
Acute diarrhea means that it has been going on for less than 4 weeks.

Infection can be viral or bacterial, viral is the more common.
During an infection, the bowel is not able to absorb foods so diarrhea occurs. You may want to consider the following:
(a)resting the bowel- use fluids to make sure that you stay hydrated but hold off solid food.
In general this is done till there is a 4 hour window with no symptoms

(b)over the counter aids like peptobismol or lomotil may help

(c)probiotics- these have been shown to decrease diarrhea- can be used on their own on in yogurts with probiotics


If the diarrhea has been occurring for more than 4 weeks then it would be considered chronic.
Causes include: (a)infection
(b)irritable bowel syndrome
(c)hormone causes like high levels of thyroid hormone
(d)diabetes
(e)inflammatory bowel disease- crohns or ulcerative colitis
(f)side effect of medication
(g)food allergy or sensitivity

If this is the case, and the diarrhea has been ongoing for 4 weeks or more then you should see your doctor.
You would need to be examined and a stool sample sent to the lab.
Blood tests would also be needed

SUMMARY: (1) if recent , more likely due to infection- rest bowel , use enough fluids, probiotics, over the counter meds
Restart food after 4 hours of no symptoms

(2)if long term/chronic- would need to be examined

I hope this helps, feel free to ask any other questions

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