Brief Answer:
Details below!

Detailed Answer:
Hi Dear,
Have gone through your query.
I appreciate your concern.

Firstly, I'd like to answer your second question. The problem that you are facing is called pruritus ani. Pruritus ani is a bothersome and sometimes intense itching or burning sensation of the skin around the anus. The most common complaint is an irresistible urge to scratch. Whether it is Pruritus ani is diagnosed by an examination of the skin around the anal area. The appearance of the skin will vary, depending on the severity and the length of time the condition has been present.

It may start with redness of the skin and can progress to thickening of the skin. It may also lead to cracks and open sores.

Some of the important causes of pruritus ani are -

Diet: Certain foods can produce irritation to the skin when stool is passed. The most common ones are products containing caffeine (coffee, tea, colas, and chocolate), spicy foods, dairy products, beer, acidic foods like citrus fruits, tomatoes, and nuts.

Stool-Excessve hard stool,It can be made soft by taking lactulose solution while going to bed.
Hemorhoids and fissures usually present with mild bleeding and will not settle down on their own.

Now let's move to your first question-

Loose stools, burning pain in intestinal regions plus a feeling of heaviness, bloating and tightness in gastric region is indicative of gastroentritis associated with gastritis.With gastroenteritis, the main symptoms you probably have are watery loose stools with stomach pain cramping and heaviness.

Gut flora is the complex community of microorganisms that live in the digestive tracts of humans,The intestinal microflora is a complex ecosystem containing over 400 bacterial species. Anaerobes outnumber facultative anaerobes. The flora is sparse in the stomach and upper intestine, but luxuriant in the lower bowel.Deplinished gut flora lead to various problems with digestive system including loose stools.

As you are already on prebiotics and pobiotics, I would advice you few tests to rule out the cause of problem

Ultrasonography whole abdomen to rule out inflammation or any other major problem.

Routine and microscopy of your stool to find out whether it is viral or bacterial infection.
Please consult your gastroenterologist for the same.

Till the time tests are done, please take Omeprazole/Pantoprazole 40mg once daily before breakfast along with your probiotics.

Apart from medicines you are on some general advises are to -

Avoid dairy product
Drink XXXXXXX warm water with some honey in it in morning
Eat a lot of vegetables and green salad
Don't eat meat products specially red-meat
No Burger, Pizza and fries

Try to follow a vegan/mediterrian diet as much as possible
Ispaghula husk should be taken 2tsf mixed in a glass of water before sleeping every night

Follow up with results of test

Regards

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