Brief Answer:
Chronic gastroenteritis.

Detailed Answer:
Hi,
Firstly thanks for choosing HealthcareMagic for your query.

As per your query most likely you are having severe gastroenteritis.
Gastroenteritis is inflammation of gastric mucosa due tio toxins released by bacteria or protozoa. Commonly its viral limits itself in 7-10 days,But in your case as it is already more then 10 days so it appears to be caused either by bacterial or protozoal infection.
Initially i would advice you to go for stool routine and microscopy testalong with culture and sensitivity test to rule out to rule out Bacterial or Protozoal infection and to see the sensitivity of various antibiotics on that bacteria or protozoa.As therapy with antibiotic has already been taken this test should be done asap.

Apart from imodium(Looeramide) which could be taken upto 16mg per day in three divided doses, I would suggest you to Rifaximin(Rifnim) 400mg twice daily along with Metronidazole(Metrogyl) 400mg thrice daily.

Isaphghullu husk should be taken twice daily.It will increase bulk of stool and bowels normal.
Cap Aristrozyme should be taken thrice daily 10 minutes before taking food.They are digestive enzymes and help in food digestion.
An antispasmodic like dicyclomine 10mg(Spasmindon) twice daily can be taken to decrease the frequency of stools.
See theory is that-
Our gut has colonies of good bacterias which help Digest and Absorb Foods. The most plentiful and important bacteria in the small intestine is the Lactobacillus species. Lactobacillus helpsferment indigestible carbohydrates and, as I mention below, supports the breakdown of sugars in dairy products, which are a common source of food sensitivities.The gut flora helps to neutralise some of the toxic by-products of digestion, reduce harmful substances (such as toxins and carcinogens), and discourage 'bad' bacteria and yeasts. It also helps to stimulate the digestive process and aid the absorption of nutrients, as well as producing vitamins including B and K. Probiotics are live bacteria and yeasts that are good for your health, especially your digestive system. Due to toxins released these good bacteria's are killed leading to symptoms you are having.

So get a stool test as suggested and take all tablets i adviced.
If possible an ultrasound abdomen should be done to rule out any other possibility.
Follow up after 3 days.
General precautions-
Eat light and easily digestible food.
Avoid meat.
Try boiled food(Vegetables) with spices and herbs for a week.
Drink plenty of orange juice and coconut water.
keep yourself hydrated.

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