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