Brief Answer:
Yes there are some general and pathological causes for bleeding with stools

Detailed Answer:
Hi there,
Thanks for choosing this forum for your query.

There are many causes ranging from harmless illness to life threatening disease conditions which can cause bleeding with stools. Usually the blood will be bright red if the bleeding is from the site closer to the anus or if it flows freely and rapidly from the small intestine; if the blood remains in the gut for a longer time without getting passed in stools then the bacteria break down the blood cells and cause the black color so is the reason the stools are black in color sometimes.
You have not specified the color of your stool in details hence would suggest you common causes for both upper and lower bleeds.

Common Causes not related to any specific disease.

Smoking, Regular alcohol intake, chewing of betel leaves or tobacco.
Eating of spicy food and oily food.
Stress, strenuous exercise can sometimes cause.
Intake of any medicines or Drugs.


Anal Lesions:
Ulcerative colitis, Crohn’s disease, Inflammatory bowel disease, Gastroenteritis(upper gi usually)
Diverticulitis
Fissure in ano
Piles or hemorrhoids
Rectal injury

So they are the most common causes as you have not mentioned any history of yours kindly go through common causes first.If that's not your case then investigation of anal canal should be done by proctoscope to rule out fissure,Hemorrhoid etc. an ultra sound abdomen should be done initially to rule out chances of inflammatory bowel disease.

Do you strain a lot while passing stools?
Are you constipated?Or do you ever feel constipated while passing stools?
Whats your diet schedule?
Hope i answered your query well please do answer the questions.

Waiting.

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