At a glance
Stool softeners are one of the most important parts of fissure management. Hard stools re-injure the fissure with every bowel movement. Soft stools allow the fissure to heal. This guide covers the types available, how they work, and how to use them effectively.
Why soft stools matter
The fissure cycle: hard stool passes over the tear, re-injuring it. The re-injury causes pain and spasm, which reduces blood flow, which slows healing. By the time the next bowel movement arrives, the fissure has not had a chance to heal — and the cycle repeats.
Soft stools break this cycle. When stool passes without creating trauma, the fissure can begin to heal.
Types of stool softeners
Osmotic preparations
How they work: Draw water into the bowel, softening the stool.
Common examples: Macrogol (Movicol, Laxido), lactulose.
What people report: Effective and well tolerated. Macrogol is generally preferred over lactulose because it causes less bloating. The dose can be adjusted to achieve the right stool consistency.
Stool softeners (emollient)
How they work: Reduce the surface tension of the stool, allowing water to penetrate it.
Common examples: Docusate sodium.
What people report: Gentle and well tolerated. May be less potent than osmotic preparations for significant constipation. Often used alongside other measures.
Fibre supplements (bulk-forming)
How they work: Absorb water and add bulk to the stool, making it softer and easier to pass.
Common examples: Psyllium husk (Metamucil, Fybogel), methylcellulose.
What people report: Effective when taken with adequate water. Need to be introduced gradually to avoid bloating. Our psyllium guide covers these in detail.
Finding the right balance
The goal: stools that are soft and well-formed. Think type 3 or 4 on the Bristol stool scale — smooth, easy to pass, and formed (not liquid).
- Too hard: Increase the softener dose, add more water, increase fibre
- Too soft: Reduce the softener dose, add fibre to add bulk
- Just right: Maintain the current approach
This balance takes trial and adjustment. It is normal to need a week or two to find the right combination.
Practical tips
- Take softeners daily, not just when you feel constipated — consistency is key
- Drink adequate water — softeners work by drawing water into the stool, so hydration is essential
- Take them at the same time each day — builds a predictable routine
- Do not rely on softeners alone — diet (fibre from food), hydration, and movement all contribute
- Continue after the fissure improves — stopping too soon is the most common cause of recurrence