Anal bleeding is a common symptom of intestinal and rectal disorders. Anal blood can indicate a relatively minor problem, however it may also be caused by a serious disease. It is usually fairly easy to diagnose by performing a clinical examination and asking the patient for precise information about any other symptoms they are experiencing. As a general rule, any kind of anal bleeding should be checked by a doctor. This article will present several causes of anal bleeding (not a comprehensive list), as well as the therapies available to treat the related diseases.


Many people suffer from haemorrhoids. The main symptom is usually anal bleeding, however they can also cause itchiness and sometimes a prolapse (protrusion of part of the rectal wall) is the dominant symptom. Pain is not a typical symptom. Haemorrhoids are not dangerous and there are many ways of treating them. The cornerstone of every therapy is to treat any constipation the patient may be experiencing, because the patient should avoid straining themselves during bowel movements. There is no scientific evidence confirming the effectiveness of haemorrhoid creams, which are often the main therapeutic approach used. However, medications that constrict the veins and promote the draining of veins can at least temporarily reduce the discomfort. If these conservative therapies do not prove successful, it is worth investigating whether surgery might be necessary. Today’s surgical techniques are almost painless and usually the patient can return home after just a few days.


Anal fistulas

A fistula is a small channel (i.e. a tube-like connection) that can develop between the rectum and the skin. Bleeding accompanied by a discharge of pus is a common symptom of an anal fistula. Often the formation of a fistula is preceded several weeks earlier by a painful abscess. The standard therapy for an anal fistula is surgery. However, fistula operations are quite difficult, as it is important to retain the integrity of the anal sphincter. The choice of surgical procedure, the experience of the surgeon and any previous operations the patient has undergone will all have a significant effect on the effectiveness of the surgery and the retention of continence after the procedure (i.e. the ability to control bowel movements). The most promising development in fistula surgery is a new surgical technique called the LIFT operation (ligation of intersphincteric fistula tract) – it has a high success rate and a very low rate of incontinence. During the operation, the fistula is removed and the gap between the internal and external parts of the sphincter is closed.

Anal fissure

An anal fissure is an elongated wound (tear) at the edge of the anus. Although bleeding does occur, the main symptom is very strong pain, mainly during bowel movements. 80–90% of these wounds heal by themselves. But they can become chronic wounds that cause problems for weeks or even months at a time. Conservative treatments of chronic anal fissures involve gentle laxatives and ointments that slightly reduce the pressure on the sphincter to improve circulation in the affected area. However, less than 30% of patients achieve long-term success with this approach.
 If conservative treatment has not been successful, many people opt for surgery. The operation usually involves removing the chronic wound and leaving it open, so that a new, smooth wound is formed that will heal in just a few weeks.

Chronic anal eczema

Chronic anal eczema is characterised by an irritating itchiness and sometimes also a burning sensation. Slight traces of blood on the toilet paper are also common and occasionally result from frequent scratching. This condition is usually caused by excessive anal hygiene, because moist toilet paper and special soaps can trigger allergic or toxic reactions. It is not uncommon for the skin to develop a bacterial or fungal infection as well. A microbiological smear test can help clarify the situation. Patients with this condition are advised to stop using all potentially allergy-causing materials and apply cortisone cream to the affected area.  Afterwards lipid replenishing ointments can be used to sooth the skin. If a bacterial or fungal infection is detected, this needs to be treated separately.

Bowel/rectal cancer

Anal bleeding is often the first sign of bowel or rectal cancer. In addition to visible blood in the stool, altered bowel movements are another early indicator of bowel cancer – particularly fluctuations between diarrhoea and constipation. From the age of 50 onwards, the risk of this type of cancer increases dramatically, which is why people of this age should have regular colonoscopies. The only therapy that can successfully treat these types of cancer is the surgical removal of the affected part of the intestine. This operation is now a minimally invasive procedure, which means it is carried out through very small incisions and the surgeon is guided by video images. Depending on the diagnosis, rectal cancer may need to be initially treated with radiation therapy and chemotherapy may also be required. This reduces the risk of the tumour returning in the same region.

Article from PD Dr. Med Daniel Dindo, surgeon specialiasing in coloproctology, and Dr. Med. Friederike Remmen, surgeon specialiasing in proctology.


• Rectum: The rectum and the anal canal form the final section of the large intestine

• Prolapse: Protrusion of part of the rectal wall

• Fistula: Pathological, tube-like connection (channel) between a hollow organ (e.g. the rectum) and the skin

• Abscess: Build-up of pus within a newly formed tissue cavity

• Continence: The ability to withhold and control the excretion of urine and faeces