Brief Answer:
hold off solids, fluid and electrolyte replacement, probiotics, peptobismol

Detailed Answer:
HI, thanks for using healthcare magic

Normally when a person diarrhea, it means that the intestines are irritated or inflamed.
They are not ready to absorb any food, if solid food is used, it would unfortunately irritate the intestines further and this would delay healing and the diarrhea would continue for longer.

This means that he should: (1) hold off ALL SOLID FOOD till there is a 4 hour window of no diarrhea
When he goes 4 hours with no diarrhea, then he can start back on solids but should start with toast, biscuits and other dry foods

(2)it is good that he is using fluids such as the soup. It would best to consider oral hydration packets that are sold for diarrhea/vomiting or a sport drink such as gatorade
The oral hydration drinks or sport drinks would give him both fluids and electrolytes

(3)probiotics would help to heal the colon

(4)medication can sometimes keep the infection inside the colon so it is only used if the diarrhea has been going on for a long period of time (more than 7 days ) or it is very severe
Peptobismol or lomotil are used

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

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