Brief Answer:
Workup needed to determine cause

Detailed Answer:
Hello and Welcome

I appreciate your concern

If the colonoscopy was normal, then malignancy is ruled out. Inflammatory bowel disease, IBS, external hemorrhoids, anal fissure and diverticulitis are possibilities with your description. Stool for ova and parasite and routine exam should be done. Gastroenteritis/ dysentery and parasitic infestation can also present with tenesmus / rectal pain that is spasmodic. Colonoscopy is also the test of choice for diagnosing IBD. Since it was normal, I would assume IBD would also not be the cause. Local examination for hemorrhoids and anal fissure would be required as both can lead to constipation and rectal pain. If no cause is found then IBS can be worked up clinically as its a diagnosis of exclusion. Rifaximin , mebeverine and eucarbon are indicated in the treatment of IBS and can be advised in consult with your doctor. For now Hyoscine butylbromide can be taken for relief from the spasms.


Wishing you best of health

Thanks

Let me know if you have any query

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Dr. M.S. Khalil

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