Brief Answer:
Clinical evaluation- investigations- avoidance of instigating factors.

Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: 28/female - history of severe diarrhea on plain milk or water melon - suffered from severe diarrhea in Feb - stomach cramps appear again for short duration at regular interval post afternoon - tried Ulgel

This history is indicative of intolerance to Milk and milk products. At the same time, you will be allergic to many more products.

The only way to know this is as follows:
You have to practically make a list of foods and beverages:
- The ones fully tolerated on one page
- The ones which would have caused even a small problem to be written on the other page.

Simultaneously you have to undergo a battery of investigations:
- Blood, urine and stool:routine investigations and in additions liver function tests and thyroid function tests.
- Ultrasonography of the abdomen / CT scan of the whole abdomen if there is any doubt in the Ultrasonography (to confirm).
- Colonoscopy helps.
- If there is an evidence of infection, get a course of an antibiotic, metronidazole for 5 days. Continue probiotics, activated charcoal,
- All under the care and guidance of a Gastroenterologist.

- Avoidance of the instigating foods, food products, spices, anything which you eat and drink will help you a lot.
- Rest of the treatment as per the findings of the reports of the investigations and findings on actual clinical evaluation, examination by a Gastroenterologist.
-There is a definite role of control of stress and anxiety as they help to control the problem.
- The symptomatic relief medicine in such a case are all prescription based and hence will be written by your Doctor.

I hope this answer gives you an idea to get a proper diagnosis and to get treated according to the cause.Please feel free to ask any relevant questions or if you feel that there is a gap-of-communication.

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