At a glance
When a fissure drags on, many people start looking at supplements. The cupboard fills up: vitamin E, zinc, vitamin C, B vitamins, fish oil, probiotics, collagen.
The honest picture:
- There is little or no clinical evidence that any oral supplement heals an anal fissure.
- Some people feel certain supplements helped, usually alongside other treatment.
- Several common supplements have real downsides at high intake.
- Some can affect bowel habit, bleeding or blood pressure.
None of these is a cure. The approaches with the clearest evidence remain soft, regular stools and, where needed, prescribed treatment. If you take supplements, tell your clinician and pharmacist what they are.
This guide does not give doses. Labels and your pharmacist or GP are the right sources for that.
What people report trying
Vitamin E. Taken by mouth, applied as oil, or used as a suppository. People mostly describe a soothing effect on sore skin rather than faster healing. A few found the oil made them itch. There is no good evidence that it heals fissures. The separate guide on vitamin E suppositories covers this in more detail.
Vitamin B6. The idea that B6 helps fissures circulates online. A small number of people describe trying it. Some say it eased things briefly; some found it constipating. One recurring warning in the accounts is numbness in the hands or legs at high intake.
Zinc. People take it because it is linked to wound healing. Some were advised to take it by a clinician after a deficiency was found. Others took it on their own. Most noticed no clear effect on the fissure.
Vitamin C. Taken for immune support or healing. High amounts can cause loose stools and stomach upset, which is probably why a few clinicians’ advice lists ask people to avoid vitamin C tablets while healing. It is not something clinicians suggest as a way to soften stools.
L-arginine. This one is often confused. Small studies have looked at L-arginine as a gel applied to the area, because it may help relax the sphincter and improve blood flow. Taking it by mouth is different. People who tried tablets generally noticed no local effect.
Omega-3 and flaxseed. Fish oil and flaxseed oil are taken for general inflammation or to help stools pass more easily. Ground flaxseed also adds fibre. Reports are mixed.
Probiotics. Some people found their bowel habit became more regular, especially those with IBS or after antibiotics. Others noticed nothing, and a few felt more constipated. A dietitian’s suggestion people mention: if nothing changes after about a month, it may not be worth continuing.
Collagen. Taken in the hope of making the skin more elastic. Collagen is broken down during digestion like other proteins. There is no evidence it targets the anal skin.
What the evidence says
- No oral supplement has good trial evidence for healing anal fissures.
- Topical L-arginine has some early study results, but it is not standard treatment.
- Zinc, vitamin C and protein matter for healing in people who are deficient. Extra does not seem to help people who are not.
- Probiotic evidence for constipation is modest and depends on the strain.
- Stool consistency is the factor most clearly linked to fissure healing.
Accounts where a supplement “worked” usually involve other changes at the same time: a softener, a prescribed cream, more water. It is hard to know which made the difference.
Cautions people do not always expect
Vitamin B6 and nerves. Long-term high intake of B6 is linked to nerve damage. Symptoms include numbness, tingling or burning in the hands and feet. These can be slow to settle after stopping.
Zinc and copper. Taking a lot of zinc for a long time can lower copper levels. It can also cause nausea or an upset stomach.
Vitamin E, fish oil and bleeding. These may affect how easily you bleed. This matters if you take blood thinners, or are about to have surgery.
L-arginine and blood pressure. It can lower blood pressure. That may matter if you use GTN ointment or take blood pressure medicines.
Constipating ingredients. Iron and calcium can firm up stools. Some people chose a multivitamin without them. If a clinician has prescribed iron, do not stop it for this reason; ask how to manage stools alongside it. Iron also commonly turns stools dark, but black, sticky, tar-like stools, or dark stools with dizziness or feeling faint, need urgent review.
Mineral oil and vitamins. Long-term mineral oil laxatives can reduce absorption of vitamins A, D, E and K. A few people found low vitamin D on a blood test after months of use.
When a deficiency is worth checking
Some people’s accounts describe a fissure period that included a big diet change, weight loss, hair loss, mouth ulcers or exhaustion. A blood test sometimes found low vitamin D, B12 or iron.
These symptoms are a reason to see your GP rather than to start more supplements. Weight loss without trying always deserves a conversation.
Some people were told by alternative practitioners that yeast or a hidden intolerance was stopping their fissure healing. In at least some accounts, an itchy, sore area turned out to be a different skin condition once a doctor examined it. A persistent rash or itch is worth having looked at.
Practical points people raise
- Keep a list of everything you take, with the strength printed on each label.
- Show that list to your pharmacist before adding anything new.
- Change one thing at a time so you can tell what is having an effect.
- Treat supplements as an addition to, not a replacement for, prescribed treatment.
- Stop and seek advice if you notice new symptoms after starting something.
When to seek care
Speak to your GP or pharmacist if:
- You notice numbness, tingling or burning in your hands or feet
- You have lost weight without trying, or have ongoing tiredness or hair loss
- You take blood thinners or blood pressure medicines and want to add a supplement
- The fissure has not improved after several weeks of steady self-care
Get urgent help (NHS 111 or your local urgent care line) if you have:
- Heavy bleeding, or bleeding that does not stop
- Black, tar-like stools, or feeling faint, whether or not you take iron
- Severe pain that keeps getting worse
- Fever, swelling or discharge near the anus
Call 999 or go to A&E if the bleeding is heavy or you feel faint, or if you have swelling of the lips, face or throat, or trouble breathing, after taking a supplement.