Do doctors need to do a rectal examination to diagnose a fissure?

Not always. Many fissures can be diagnosed by visual inspection alone — the doctor gently separates the buttocks to see the anal margin. A digital rectal examination (inserting a gloved finger) is sometimes done but may be deferred if the area is too painful. The doctor will explain what they need to do and why, and will not proceed without your consent.

Is the examination painful?

The visual inspection itself should not cause pain — it involves looking, not touching the fissure. If a digital examination is needed, it may cause some discomfort, particularly if the fissure is acute. A good clinician will be gentle, use lubrication, and stop if you need them to. You are always in control of what happens.

Can a GP diagnose a fissure or do I need a specialist?

Most fissures can be diagnosed by a GP based on your symptom description and a visual examination. A referral to a specialist (colorectal surgeon or gastroenterologist) is typically made if the fissure does not respond to initial treatment, if it is in an unusual location, or if further investigation is needed. Many people are diagnosed and treated successfully by their GP.

What if I am too embarrassed to be examined?

This is extremely common. Doctors who work with these conditions see them routinely and approach them with the same professionalism as any other examination. If you are anxious, you can ask to bring someone with you, request a specific gender of clinician, or ask the doctor to explain each step before they do it. Your comfort matters, and good clinicians will accommodate your needs.

How doctors diagnose a fissure

At a glance

Diagnosing an anal fissure is usually straightforward. In most cases, a doctor can identify a fissure based on your symptoms and a brief visual examination. The process is quicker and less invasive than most people expect.

This guide explains what happens during diagnosis, what the doctor is looking for, and how to prepare for the appointment.

The symptom history

The first and most important part of diagnosis is your description of what you are experiencing. The pattern of symptoms often points clearly to a fissure before any examination takes place.

Key questions your doctor will typically ask:

When does the pain occur? Pain during and especially after bowel movements is the hallmark of a fissure
What does the pain feel like? People commonly describe sharp, tearing, or burning pain
How long does the pain last? Post-bowel-movement pain lasting minutes to hours is typical
Is there bleeding? Bright red blood on paper or in the bowl, usually small amounts
How long have you had symptoms? This helps distinguish acute from chronic fissures
What are your bowel habits like? Constipation, hard stools, or straining are common triggers
Have you tried anything? Knowing what you have already done helps guide the next steps

The examination

Visual inspection

The most common examination method is simple visual inspection. The doctor will ask you to lie on your side (usually left side, knees drawn up). They will gently separate the buttocks to see the external anal area.

This is usually all that is needed. A fissure at the anal margin is often clearly visible — a small linear tear, usually at the posterior midline. The doctor may also look for:

A sentinel pile (skin tag) near the fissure — suggests chronicity
Signs of swelling or inflammation
The location of the fissure (midline vs off-midline)
Any other visible conditions

Digital rectal examination

In some cases, the doctor may want to perform a digital rectal examination (DRE) — inserting a lubricated, gloved finger into the anal canal. This helps assess:

Sphincter tone (how tight the muscle is)
The presence of internal conditions
The extent of the fissure

If the area is very painful — which is common with acute fissures — the doctor may defer this examination. A fissure can often be diagnosed without it, and causing unnecessary pain is not helpful.

Specialist examination

If a referral to a specialist is needed, additional examination might include:

Anoscopy — a small, lubricated instrument used to see inside the anal canal. This is brief and may cause some discomfort.
Examination under anaesthesia (EUA) — for cases where pain prevents adequate examination, the specialist may recommend looking while you are under anaesthesia. This is typically done as a day procedure.
Anal manometry — a pressure test that measures sphincter function. Not routine but sometimes used to guide treatment decisions.

What the doctor is looking for

Beyond confirming the fissure, the doctor assesses:

Acute vs chronic — acute fissures look like a fresh tear; chronic fissures may have thickened edges, a sentinel pile, and exposed muscle fibres
Location — the vast majority are posterior midline; fissures in other locations may need further investigation
Complexity — is this a simple fissure, or are there signs of an underlying condition?
Coexisting conditions — hemorrhoids, skin tags, or other issues that may need addressing

What happens after diagnosis

Once a fissure is confirmed, the doctor will typically:

Explain what a fissure is and why it has developed
Recommend first-line treatment — usually dietary changes, stool softening, and possibly a topical prescription
Set a timeframe for review — commonly four to six weeks
Explain when to come back sooner if symptoms worsen
Refer to a specialist if the fissure is chronic, atypical, or has not responded to initial treatment

Preparing for your appointment

To make the most of your appointment:

Write down your symptoms — when they started, their pattern, what makes them better or worse
Note your bowel habits — frequency, consistency, any straining
List what you have tried — any over-the-counter treatments, dietary changes, or home remedies
Prepare questions — anything you want to ask
Know that it is okay to be nervous — the doctor expects this and will work at your pace