Straining can lead to hemorrhoids as well as constipation. I would assume that a colonoscopy has been performed to look for anatomic abnormalities.
If the symptoms continue, you can consider more specialized testing, such as anorectal manometry as well as colonic motility studies.
If the symptoms continue, IBS medications like Zelnorm may be of benefit.
These options can be discussed with your personal physician.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
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