Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice.
Considering the stomach pain that comes and goes, the feeling of needing to relieve bowels and the fact that he relieved bowels several times yesterday (
diarrhea), in my opinion he might have an
enteritis.
Enteritis is an inflammation of the
small intestine that may also involve stomach, and probably it is caused by a viral infection.
Your cousin can use
buscopan 10 mg for cramps pain relieve,
Ranitidine 150 mg for stomach pain.
He has to use oral rehydration solutions because he has lost liquids and electrolytics of the body, and also he can use probiotics to help improve the diarrhea.
If these symptoms persist more than four days and if he notices blood in the stool or if he has fever , he has to seek medical attention.
Hope I have answered your query. Let me know if I can assist you further.