At a glance
Diltiazem cream is one of the most commonly prescribed topical treatments for anal fissures. It works by relaxing the internal sphincter muscle, which reduces spasm and improves blood flow to the fissure site. It is often prescribed as an alternative to GTN (glyceryl trinitrate) cream, particularly for people who experience headaches with GTN.
This guide covers what the experience of using diltiazem is actually like — the practical details that your prescription label does not cover.
How it works
Diltiazem is a calcium channel blocker. The internal anal sphincter muscle relies on calcium to maintain its tone and contraction. By blocking calcium channels locally, diltiazem relaxes the muscle, which:
- Reduces sphincter spasm — the primary cause of restricted blood flow
- Improves blood supply to the fissure site — supporting healing
- Decreases pain associated with the spasm cycle
It does not heal the fissure directly. It creates the conditions in which the fissure can heal itself.
The typical treatment course
Getting started
Diltiazem cream for fissures is usually compounded by a pharmacy — it is not typically available as a standard off-the-shelf product. Your clinician will write a prescription specifying the concentration.
The usual application:
- A small amount (roughly pea-sized) applied to the anal area
- Typically two to three times per day
- For six to eight weeks minimum
What to expect in the first week
- Mild burning or stinging at the application site — this is the most common initial experience. It usually settles within a few minutes and tends to diminish over the first few days as the area adjusts.
- No dramatic improvement yet — the cream needs time to take effect
- Occasional headache — less common than with GTN but possible
- A slight sense of the area being less tense — some people notice this early
Weeks two to four
This is when most people begin to notice meaningful changes:
- Bowel movements become less painful as sphincter spasm reduces
- Post-bowel-movement burning duration decreases
- The sense of tightness and clenching eases
- Confidence in the treatment begins to build
Weeks four to eight
Continued improvement for many people:
- The fissure is actively healing in the less-tense environment
- Pain continues to decrease
- Some people describe being able to resume activities they had avoided
- The routine of application becomes habitual
Practical application tips
How to apply
- Wash your hands thoroughly
- Squeeze a pea-sized amount onto your finger (some people use a gloved finger or cotton bud)
- Apply to the external anal area — you do not need to insert it
- Some clinicians advise a small amount just inside the canal; follow your specific instructions
- Wash your hands again
Timing
People describe the best results with:
- After sitz baths — the tissue is clean and warm, which may improve absorption
- After bowel movements — clean, warm tissue; the treatment can help with post-movement spasm
- Before bed — a consistent evening application
Storage
- Store as directed on the label — usually at room temperature
- Check the expiry date — compounded creams may have shorter shelf lives than commercial products
Managing side effects
Burning on application
The most common side effect. Strategies:
- Apply a very thin layer initially and increase gradually
- Ensure the area is completely dry before application
- If burning persists beyond a few minutes, try a smaller amount
- This effect typically diminishes over the first week
Headaches
Less common with diltiazem than GTN, but possible:
- Usually mild and manageable
- Paracetamol can help
- If headaches are severe or persistent, discuss with your prescriber
What to report to your prescriber
- Severe or persistent headaches
- Dizziness or feeling faint
- Rash or significant skin irritation
- No improvement after six weeks of consistent use
- Any side effects that concern you
The bigger picture
Diltiazem cream is one part of the treatment approach. It works best alongside:
- Consistent stool management — fibre, water, stool softeners
- Regular sitz baths
- Good toilet habits — no straining, responding to urges promptly
The cream addresses the sphincter spasm component. Stool management addresses the re-injury component. Together, they give the fissure the best chance of healing.