How deep should I apply rectal ointment?

Most rectal ointments for fissures are applied to the anal margin and just inside — roughly to the depth of the first knuckle of your little finger. The fissure is typically at or just inside the anal opening, so deep insertion is not needed. If your doctor or pharmacist has given specific instructions about depth, follow those. If you are unsure, ask at your next appointment.

How much ointment should I use?

A pea-sized amount is sufficient for most applications. For GTN (Rectogesic), the packaging often includes a dose line — a thin strip along the finger. More is not better. Excess ointment increases the risk of side effects like headaches and dizziness without improving healing. Consistent small amounts applied regularly are more effective than larger amounts applied irregularly.

Should I use my finger or an applicator?

Both work. Many people use a gloved fingertip, which gives control over placement and pressure. Some people prefer a cotton bud, a finger cot, or a small applicator tip. The choice is personal. What matters is that the medication reaches the area and that you are comfortable with the method. If using GTN, a glove or finger cot is recommended to prevent the medication absorbing through your finger and causing a headache.

Should I apply before or after a bowel movement?

Ideally, apply after a bowel movement once you have cleaned up. The medication will stay in contact with the area rather than being wiped away. If you typically have a bowel movement at a predictable time, build your application schedule around it. If your bowel timing is unpredictable, apply at your scheduled times and reapply after a bowel movement if it happens within an hour of application.

Does it hurt to apply the ointment?

Some people experience brief stinging or burning when applying, particularly to broken or irritated skin. This usually settles within a few minutes. If pain during application is severe or getting worse with each use, let your doctor know. Applying gently and using the minimum effective amount can help. Some people find that applying after a warm sitz bath, when the area is relaxed, reduces discomfort.

Do I need to apply internally or just externally?

This depends on your specific prescription and your doctor's instructions. Most topical fissure treatments are meant to be applied around the anal margin and just inside the opening — not deep internally. The goal is to deliver the medication to the internal sphincter muscle, which sits just beneath the surface at the anal verge. A thin layer applied around and just inside is typically what is meant. If your instructions say 'apply internally' and you are unsure what that means in practice, ask your prescriber to clarify.

How to apply rectal ointment properly

Published 12 March 2026 ·Last reviewed 12 March 2026 by the editorial team ·How we create our content

At a glance

You have been prescribed a rectal ointment — GTN, diltiazem, nifedipine, or something similar — and the instructions that came with it leave questions. How deep? How much? What do they mean by “apply internally”? Should you use your finger? What if you have a bowel movement right after?

These are some of the most frequently asked questions across fissure forums. They come up because the instructions are often vague, the area is sensitive, and the last thing you want is to do it wrong.

This guide covers the practical technique of application — the specific how-to that our broader guide on applying topical treatments complements with information about side effects, course duration, and when to go back to your doctor.

This is not a replacement for your prescriber’s instructions. Always follow the guidance you were given. What follows reflects the most commonly described approaches and answers the practical questions that come up most often.

Before you apply: preparation

Good preparation makes the process quicker and less stressful.

What you need:

Your prescribed ointment or cream
Disposable gloves or finger cots (especially important for GTN)
Moist wipes or a washcloth
A mirror (optional — some people find it helpful initially, others do not)
A thin pad or liner for your underwear

Position options: People describe several positions for application:

Standing with one foot raised — on a stool, the edge of the bath, or the toilet lid. This is the most commonly described position.
Lying on one side with knees drawn up — gives good access and can be more comfortable if the area is very painful.
Squatting — some people find this opens the area most effectively.
Sitting on the toilet — practical but can be awkward for reaching.

There is no single correct position. Use whichever gives you comfortable access and allows you to see or feel what you are doing.

The application technique: step by step

Step 1: Wash your hands

Thoroughly, with soap and warm water. Even if you are going to wear gloves.

Step 2: Put on a glove or finger cot

This is particularly important with GTN (Rectogesic). GTN is absorbed through skin — if it gets on your bare finger, you may develop a headache from the medication absorbing through your fingertip. A disposable glove or a finger cot prevents this.

For diltiazem and nifedipine, gloves are still recommended for hygiene, though the absorption risk is lower.

Step 3: Dispense the right amount

How much: A pea-sized amount. For GTN, the packaging may include a measuring strip — follow it. For compounded creams, a small dab on the fingertip is sufficient.

The instinct to use more is understandable — more cream feels like more treatment. But excess ointment does not speed healing. It increases side effects and creates mess. A small, consistent amount applied regularly is what works.

Step 4: Apply around the anal margin

Gently spread a thin layer of ointment around the outside of the anus. Cover the area evenly. This is where the external portion of the internal sphincter sits, and the medication works through the skin to reach the muscle beneath.

Step 5: Apply just inside the opening

Using your gloved fingertip, gently introduce a small amount of ointment just inside the anal opening. The depth most people describe is to the first knuckle of the little finger — roughly 1 to 2 centimetres.

Key points:

You do not need to push deep inside. The fissure is typically at or just inside the anal margin.
Be gentle. The area may be sore, and forceful insertion can cause pain or re-injury.
If it hurts significantly, stop. Apply externally only and discuss internal application with your doctor at your next appointment.
Some people find that bearing down slightly (as if beginning a bowel movement) opens the area enough to apply without pushing.

Step 6: Remove the glove and wash your hands

Even after using a glove, wash your hands thoroughly. GTN in particular can transfer to surfaces and cause headaches through secondary contact.

Step 7: Use a liner

Place a thin pad or panty liner in your underwear. Some ointment will migrate over the following hours, and a liner prevents staining and keeps the area cleaner.

Timing: when to apply

In relation to bowel movements

The ideal sequence, as described by most people:

Have your bowel movement
Clean the area gently — warm water, moist wipes, or a bidet
If you take a sitz bath, do that next
Pat dry
Apply the ointment

Applying after a bowel movement means the medication stays in contact with the area rather than being wiped away. The post-bowel-movement period is also when the sphincter may be spasming, and the medication can help address that spasm directly.

If a bowel movement happens soon after application

If you have a bowel movement within roughly an hour of applying, most of the ointment will have been wiped away. People commonly describe reapplying after cleaning up.

If the bowel movement happens several hours after application, the medication has likely been absorbed sufficiently. Reapplication at your next scheduled time is usually fine.

When in doubt, ask your prescriber. This is one of the most common questions they receive.

Application schedule

Most topical fissure treatments are prescribed two or three times daily. Common patterns people describe:

Morning (after the first bowel movement) — afternoon/evening — before bed
After each bowel movement plus before bed
Tied to existing routines — after brushing teeth, after meals, at fixed clock times

Spacing applications roughly evenly through the day gives the sphincter consistent relaxation rather than peaks and troughs. The before-bed application is widely described as particularly important — the medication works overnight while the body is still.

Common mistakes and how to avoid them

Applying too deeply

The medication does not need to go far inside. People who insert too deeply sometimes describe increased discomfort or the medication migrating away from where it is needed. The first knuckle depth is sufficient. If you are unsure, err on the side of shallower rather than deeper.

Using too much

More ointment means more side effects — headaches from GTN, itching from diltiazem — without faster healing. A thin, consistent layer is more effective than a thick, irregular one.

Applying with bare fingers (especially GTN)

GTN absorbs through any skin it contacts. Bare-finger application commonly causes headaches from the medication entering your bloodstream through your fingertip. Always use a glove or finger cot. If you have been applying bare-fingered and experiencing headaches, this may be part of the reason.

Rushing the process

Applying quickly and roughly can cause pain and potentially re-injure the fissure. People who describe the best experience take their time — a minute or two in a comfortable position, with gentle pressure, is better than a quick, uncomfortable application.

Inconsistent application

Skipping doses or applying at irregular intervals means the sphincter does not stay consistently relaxed. The fissure needs a sustained healing window. Think of it like keeping a fire burning — regular small additions of fuel work better than one large one followed by nothing.

Not completing the full course

This is the most commonly reported mistake across all fissure treatment discussions. Pain improves after 2 to 3 weeks, and people stop. The fissure has not finished healing. Stopping early is one of the most frequently cited reasons for fissure recurrence. Complete the full course your doctor prescribed — usually 6 to 8 weeks.

Making application less uncomfortable

For many people, the process is mildly uncomfortable rather than painful. But when the area is very sore, even gentle application can be difficult. Strategies people describe:

Apply after a warm sitz bath or shower. The warmth relaxes the sphincter and reduces pain on contact.
Use the minimum amount. Less ointment means less manipulation of the area.
Breathe. Slow, deep breaths during application can help prevent unconscious clenching.
Lubricate the gloved finger slightly with the ointment itself before approaching the area.
Go slowly. There is no time pressure. A gentle, gradual approach is better than a quick one.
Apply externally first to let the area adjust to the sensation before introducing any ointment internally.

If application is consistently very painful, let your doctor know. They may adjust the formulation, suggest a different application method, or investigate whether something else is contributing to the pain.

Finger cots, gloves, and applicators

Disposable gloves: The most commonly used option. Available at any pharmacy. Nitrile gloves are preferable if you have a latex allergy.

Finger cots: Small covers that fit over a single finger. Less wasteful than a full glove and equally effective at preventing GTN absorption. Some people find them easier to manage.

Cotton buds: Some people use a cotton bud for external application. This can work for spreading ointment around the margin but is less effective for introducing any ointment just inside.

Applicator tips: Some compounded preparations come with a small applicator. If yours does, your pharmacist can demonstrate how to use it.

The method matters less than the result. Whatever allows you to apply the right amount to the right area comfortably is the correct method for you.

Storage and practicalities

Store the ointment as directed — some compounded preparations need refrigeration
If you need to apply at work, keep a small kit in a bag: ointment, gloves or finger cots, wipes, a liner
Travel: carry the ointment in your hand luggage if flying (checked bag temperature changes may affect it)
Check the expiry date, especially for compounded preparations which may have shorter shelf lives

Questions to bring to your prescriber

If you are unsure about any aspect of application, these are reasonable questions to ask:

Can you show me exactly where and how deep to apply?
Should I apply internally, externally, or both?
What should I do if I have a bowel movement soon after applying?
What if I miss a dose?
How will I know the treatment is working?
When should I come back for a follow-up?

There is no question about application technique that is too basic or too embarrassing to ask. Your prescriber has answered all of them before.

When to contact your doctor

Contact your doctor if you experience:

Heavy or persistent bleeding after application
Pain that is significantly worse after applying the ointment
Signs of allergic reaction — spreading rash, swelling, or difficulty breathing
Signs of infection — increasing redness, warmth, swelling, or discharge
Fainting or severe dizziness after applying GTN
Severe headache that does not respond to paracetamol
No improvement after 2 to 3 weeks of consistent use
Any new symptoms that concern you