Understanding anal fissure through community experiences and medical research.
Community experiences, not medical advice
Last editorial review: October 2026•Next review: April 2027
What is an anal fissure?
An anal fissure is a tear or ulcer in the lining of the anal canal. It typically causes severe pain on defecation — often described as passing broken glass — and is commonly accompanied by bright red rectal bleeding, seen on the paper or in the pan. You can read the NHS overview on the NHS website.
Fissures are described as acute when they have been present for under six weeks, and chronic when they persist for six weeks or longer. Acute fissures often heal with stool softening, analgesia, and hygiene measures; chronic fissures may need topical therapy or specialist referral. This acute/chronic split is how NICE Clinical Knowledge Summaries and the 2023 ACPGBI guideline frame the pathway.
Most fissures sit in the midline (typically the back midline). Fissures that are irregular, multiple, off the midline, or appearing for the first time in an older adult are described as secondary — they warrant investigation for underlying causes such as inflammatory bowel disease (IBD), sexually transmitted infections, or colorectal cancer. Crohn's-related perianal disease is out of scope for this page.
How it is diagnosed
Anal fissure is usually a clinical diagnosis: a clinician listens to the history (severe pain on defecation, often with bright red bleeding) and examines the area. NICE CKS describes the typical findings and when to suspect a secondary cause. It is not something a webpage can confirm, and it should not be confused with haemorrhoids (piles) — the two are commonly mixed up, but the treatments and the meaning of the bleeding differ.
Hard stool is a frequent trigger, so a clinician will often ask about constipation and toileting habits. If the picture is atypical — lateral or multiple fissures, recurrence after good treatment, or a new fissure in an older adult — further investigation is advised, including for IBD where relevant. Red flags for cancer or IBD should never be sat on.
Common Symptoms
Severe, sharp pain on defecation, sometimes persisting afterwards as a burning or throbbing ache
Bright red rectal bleeding, usually small amounts on the paper or in the pan
A visible tear or a sentinel skin tag at the anal verge in chronic cases
Fear of going to the toilet because of the pain, which can worsen constipation and keep the cycle going
Spasm of the anal sphincter that makes the tear slow to heal
Common experiences people share
A cycle of hard stool → tear → pain → holding on → harder stool, which keeps the fissure open
Assuming the pain and bleeding are piles, then finding the label is a fissure once a clinician looks
Worry that surgery will cause incontinence — a real conversation to have with a specialist, not something to decide alone
Important:
The information on this page comes from community experiences and published research. It is not medical advice, not a diagnosis, and not a treatment plan. Always talk to your GP or another qualified clinician before changing how you manage your symptoms — especially if you notice red flags such as unexplained weight loss, persistent bleeding, or a change in bowel habit.
Approaches people discuss
These are options clinicians, guidelines, and community members discuss around anal fissure — not a self-treatment plan.
Established First-line self-care for acute fissure: fibre and fluids to keep stool soft, not ignoring the urge to defecate, warm baths, and simple analgesia. NICE CKS advises seeing a GP if symptoms worsen or do not improve after about seven days. Sources: NICE CKS Anal fissure; NHS Anal fissure.
Established For adults with symptoms persisting a week or more, asking a GP about rectal glyceryl trinitrate (GTN) ointment for six to eight weeks — a standard primary-care option. Headache is a common side effect and worth knowing about before starting. Sources: NICE ESUOM7; NICE CKS.
Established Specialist options for refractory chronic fissure, such as botulinum toxin injection or surgery (for example lateral internal sphincterotomy). Surgery heals many fissures but carries a risk of incontinence — a real trade-off to discuss with a colorectal surgeon rather than self-manage. Sources: ACPGBI guideline on anal fissure 2023; NICE CKS.
Established Prompt clinical review when a fissure looks secondary — irregular, multiple, lateral, or new in an older adult — because the underlying cause (IBD, STI, colorectal cancer) changes the whole care path. Sources: NICE CKS; ACPGBI 2023.
Emerging Topical diltiazem as an alternative to GTN in some UK pathways. It is unlicensed for this indication in the UK and evidence continues to evolve, so the exact place in the pathway is a clinician conversation. Sources: NICE CKS; ACPGBI 2023.
What not to self-manage
These are cautions, not approaches people discuss:
Do not assume all anal pain and bright red bleeding are piles — the pain pattern and the response to simple measures differ; a clinician needs to look before you settle on a label.
Do not sit on a persistent or atypical fissure — lateral, multiple, or recurrent fissures, and new fissures in older adults, need assessment for secondary causes such as IBD, infection, or colorectal cancer.
Do not delay GP review when red flags are present — unexplained weight loss, persistent bleeding, or a change in bowel habit are not a wait-and-see picture.
Do not self-prescribe topical treatments for months without review — GTN and diltiazem have defined courses and side effects; ongoing use without a clinician checking the picture is a frequent regret.
Do not decide on sphincterotomy from a forum thread — surgery heals many fissures but carries an incontinence risk; that trade-off belongs in a consultation, not a comment section.
Medical Research
ACPGBI guideline on anal fissure (2023)
The Association of Coloproctology of Great Britain and Ireland position statement on anal fissure, published in Colorectal Disease. It covers the acute vs chronic split, topical therapies, botulinum toxin, and surgical options, including the incontinence trade-off of lateral sphincterotomy.