IT'S not something you ever want to see when you take a peek at your business.
Blood on the toilet roll after a number two is enough to spark panic in anyone.
Before full-blown panic attack sets in, there are a number of reasons blood can appear down there - with some much more serious than others.
Though not all of these reasons are cause for alarm, you should always speak to a doctor if it is persistent.
If you are bleeding from your backside it will either be bright red blood, indicating bleeding in the lower rectum, or a very dark red colour which comes from further up in your body.
Passing dark red blood is a sign you are bleeding in your stomach or bowel or other parts of your digestive system and you should get it checked immediately.
Here, we reveal 11 reasons you may be bleeding from your bottom.
1. Haemorrhoids
Also known as piles, haemorrhoids are swellings around the anus caused by enlarged blood vessels.
Many people won't have any symptoms.
But some will notice lumps around their bottom, pain when doing a number two, an itchy bottom and bright red blood in your stool.
The exact cause of piles is not known, but the condition is thought to be caused by increased pressure in the blood vessels down there.
Symptoms will typically go away after a few days. But if your symptoms are severe, book an appointment with your GP.
2. Bowel cancer
Without doubt, one of the most serious causes of blood in your poo, is bowel cancer.
So much so, it's one of the red-flag signs you could have the disease - and if you suspect it could be the culprit, book a GP appointment straight away.
Bowel cancer, also known as colon or colorectal cancer, is the fourth most common form of the disease in the UK, after breast, prostate and lung cancers.
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More than 41,000 people in the UK are diagnosed with the disease each year, according to .
Symptoms include pain in the abdomen, a change in your normal toilet habits, a lump in your back passage, needing to strain to do a number two and blood in your poo.
3. Internal bleeding
If the blood you spot post number two is dark red, it can be a sign of internal bleeding.
It could be happening anywhere in your digestive system, from your stomach to your small and large intestines.
Bleeding like this can be a sign of cancer, stomach ulcers or severe gastrointestinal disease.
If you see dark red blood in your poo contact your doctor immediately.
4. Gastroenteritis
Gastroenteritis is a common bacterial infection that causes diarrhoea and vomiting.
The tummy bug affects people of all ages but is most common in young children.
It can be really unpleasant but normally clears up on its own in a couple of days.
The illness can cause inflammation in the stomach and colon, making it more sensitive when doing a poo.
This can cause spots of blood to appear in your stools.
5. Fistula
An anal fistula is a small tunnel that develops between the end of the bowel and the skin near the anus.
They are usually caused by an infection near the bottom causing a collection of pus in the nearby tissue, according to the NHS.
When the infection drains it leaves behind a small channel.
Anal fistulas can be uncomfortable and can cause blood in your stool.
The symptoms won't go away on their own and will require surgical treatment.
6. Fissures
An anal fissure is a tear or ulcer that develops in the lining of your bottom.
As with all small cuts and grazes, it will heal on its own within a few weeks.
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If you have a fissure you may experience pain when passing a stool and bleeding.
Your GP can help you with medication to help it heal and to ease the pain.
7. Diverticulosis
Diverticulosis is a condition that affects the bowel.
Diverticula are small bulges or pockets that can develop in the lining of the intestine as you get older.
If they become inflamed or infected it can cause pain in the lower tummy, bloating, constipation or diarrhoea and blood in your number twos.
You are more likely to get diverticula is you don't eat enough fibre in your diet.
8. Colitis
Colitis is a long-term condition that causes the rectum and colon to become inflamed.
Small ulcers will develop in the lining of the bowel, which then bleed and produce pus.
The main symptom of colitis is recurring diarrhoea, tummy pain and needing to poop frequently.
People who have colitis are also more likely to suffer other bowel conditions such as irritable bowel syndrome and Crohn's disease.
9. STIs
Sexually transmitted infections (STI) can affect the bottom as well as the penis and vagina.
Unprotected anal sex can spread STIs from person to person.
Once infected it can cause inflammation of the lining of the anus, which can lead to bleeding and pus.
You will need to see a doctor to diagnose the infection, after which you will be treated with either antibiotic, antiviral or antifungal medication depending on the type of infection you have.
10. Prolapse
It's not something anyone ever wants to experience, but your rectum can prolapse.
That means part of your rectum will protrude out through your bum.
It can happen when you are doing a number two and can be quite uncomfortable.
If you have a prolapse you may find it difficult to control your bowel movements, will have pain and will notice bright red blood in your poop.
A prolapse will not heal on its own so you need to contact a doctor straight away.
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11. Polyps
You may have heard about polyps when people talk about bowel cancer.
Polyps are non-cancerous growths that can developing on the lining of your bowel.
Bowel polyps are very common, affecting around one in four people.
They don't often cause symptoms and are only picked up during screening for bowel cancer.
But when they do cause symptoms it can be diarrhoea, constipation, mucus in your poo, blood in your poo and pain in your tummy.
In most cases polyps won't turn into cancer but some, known as adenomas, can be a risk if they are not removed.
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