Brief Answer:
IBs is a diagnosis of exclusion never first diagnosis.

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service.
I have reviewed your query and here is my advice.
Let's move to various levels involved in our digestive process which may be the culprit behind it;
Our gastrointestinal tract has a forward propulsive movement (peristalsis) that moves the food material forward as it is digested, absorbed and finally expelled as feces. Color of feves is given by a pigment secreted by liver called bile.Bile is further broken into stercobilinogen which gives color to stools.If somehow this movement gets hampered, the bowel habits would not be proper. This may lead to the formation of colonies of bad bacterias and yeast in your gut Secondly as there is diarrhea food would move fast in intestine hence bile would not be broken properly giving a greenish orangish or other tinge to stools.

Now let me give you a brief idea about what is intestinal flora?
Our body has its own environment called gut flora. Gut flora is the community of microorganisms that live in the digestive tracts of humans. A number of factors including age destroy this flora and can lead to various problems with a digestive system like indigestion, abdominal pain, belching, bloating and increased gas formation. I would suggest you start good quality probiotics for a few days
Degradation of undigested food in the intestines by the intestinal bacteria would lead to the excess gas formation.

Lastly Irritable bowel syndrome is a diagnosis of exclusion which means that when despite of all possible investigations like stool test culture colonoscopy CT abdomen liver function tests every thing is fine then it's IBS.Just because you have diarrhea gas and orange stool does not makes you a patient of IBS.
Get a stool culture done.
Liver function done
If it's normal start-

Treatment-
Cap Omeprazole 40 mg once daily in morning empty stomach 6 a.m
Tab activated charcoal twice daily 9 a.m-9 p
m.
Cap econorm thrice daily(probiotic).
Tab Dicyclomine 10 mg twice(would decrease rate of peristalysis hence would help intestine to properly break for and bile and absorb it.
All are easily available take them for 5 days and you would be fine.
If possible follow this also,
You should also take walk after meals.
-You should take small portions of food every 2 hours.
-Avoid heavy and large fatty meals.
-You should also limit intake of fizzy drinks, smoking, and excess chewing gums.
-You can take Simethicone as it helps in reducing intestinal gas.
-Activated charcoal pills can be helpful.
-Drink sufficient water.
-chew your food slowly and properly.
Don't worry labelling patient as IBS without trying medications proper investigations makes no sense.
Follow what I said and tell me how you feel in s week.
Feel free to follow up.
If you find answer helpful do rate it.
Thank you,
Dr Kumar
Gastroenterologist.

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