If you live with rosacea that manifests as facial flushing, persistent redness, or papules and pustules that look like acne but aren’t quite acne and you also struggle with bloating or IBS-type symptoms there may be a connection with a bacterial overgrowth in the small intestine.

A growing body of research suggests a subset of rosacea is linked to the gut, especially small intestinal bacterial overgrowth (SIBO).

The good news? Treating SIBO in some cases may reduce the redness on your skin.

In this article, I explain more about the link between rosacea and SIBO, how to test for SIBO, evidence-based treatment options (medical and natural), diet strategies, and other conditions commonly linked to rosacea.

Interesting facts about Rosacea

• Rosacea is very common – about 1 in 20 adults worldwide are affected.
  
• In a landmark trial, eradication of small intestinal bacterial overgrowth led to near-complete clearance of rosacea lesions and kept most patients in remission for at least 9 months. This is great news if you have been searching for causes for your rosacea and you have gut symptoms such as bloating,
  
• In some cases, Coffee may be protective: higher caffeinated coffee intake was linked to lower risk of developing rosacea.
  
• Alcohol, especially white wine and spirits, is associated with higher rosacea risk
  
• Rosacea frequently overlaps with gut and neurovascular disorders (e.g., IBS/IBD, migraines).

What is rosacea?

Rosacea is a long-term skin condition that can also affect nose, cheeks, forehead and chin.

It is a chronic inflammatory condition that primarily affects the central face.

Typical features include transient or persistent facial redness, flushing, visible blood vessels (telangiectasia), papules and pustules, and in some individuals, eye involvement (ocular rosacea).

Common signs are redness that comes and goes (flushing), visible tiny blood vessels, and small red bumps or pus-filled spots. Some people also get eye symptoms such as dryness, grittiness or soreness (this is called ocular rosacea).

Why does Rosacea make your skin red?

• If you have Rosacea the tiny blood vessels in your face open up easily and stay open for longer.
  
• Ongoing irritation causes inflammation, so your skin can feel warm, sore or tight.
  
• Over time, extra small vessels grow near the surface. These can show as fine red lines (thread veins), especially on the cheeks and nose.
  
• The nerves that control blood flow become more sensitive, so everyday things such as a hot shower or a hot drink can set redness off.

Common triggers for Rosacea

Below are some common items that can trigger a flare:

• Heat (hot weather, hot showers, saunas) or sudden temperature changes
• Hot drinks and spicy foods
• Alcohol, especially white wine and spirits
• Wind and cold air on the face
• Stress
• Harsh skincare, scrubs or perfumed products
• Underlying gut conditions such as Small Intestinal Bacterial Overgrowth and Helicobacter Pylori.

What you can do

• Be gentle with your skin: use a mild cleanser, fragrance-free moisturiser, and daily SPF. Avoid scrubs and very hot water.
  
• Manage heat: choose warm rather than very hot drinks; take lukewarm showers; protect your face from wind and sun.
  
• Know your triggers: keep a simple diary to spot patterns and make small changes that help.
  
• Look at your Gut Health and consider testing for SIBO.
  

What is SIBO — and how is it linked to rosacea?

Small intestinal bacterial overgrowth (SIBO) is a condition whereby there are too many bacteria in the small bowel, where numbers should normally be low. This overgrowth can cause bloating, gas, tummy pain, diarrhoea or constipation, and food intolerances to high fibre foods and fermentable foods.

SIBO is usually diagnosed using a SIBO hydrogen/methane breath test or, less often, by testing fluid from the small intestine.

How common is SIBO?

SIBO is more common in people with gut conditions (for example, about a third of people with IBS test positive in pooled analyses), and in those with slow gut movement, previous gut surgery, adhesions, or low stomach acid.

So… how many people with rosacea have SIBO?

Most research looks the other way round (how many people with rosacea have SIBO), so we don’t yet have a reliable percentage for “rosacea among SIBO patients.” What we can say:

People with rosacea are much more likely to have SIBO than people without rosacea.

• In a well-known trial, 46% of rosacea patients had SIBO vs 5% of controls; clearing SIBO with rifaximin led to near-complete skin remission that often lasted months.
  
• A recent meta-analysis pooling several studies found SIBO was about 3–4 times more common in rosacea than in controls, and skin signs often improved after SIBO treatment.
  

Bottom line: If you have rosacea plus IBS-type symptoms (bloating, gas, bowel changes), testing for SIBO is a very good idea PMC

What does the research say about SIBO and Rosacea?

Researchers compared people with rosacea to people without rosacea and and used hydrogen/methane breath tests to check for SIBO.

They found SIBO was much more common in people who had rosacea, and when SIBO was treated, skin symptoms improved a lot.

• How common? In this study, 52 out of 113 people with rosacea had SIBO, compared with 3 out of 60 people without rosacea. owlstonemedical.com+1
  
• What happened after treatment? People with SIBO took rifaximin for 10 days. Most (28/32) cleared SIBO, and many saw their rosacea clear or improve. Those who got placebo at first did not improve, but did improve once they later took rifaximin. Benefits often lasted at least 9 months. owlstonemedical.com+2owlstonemedical.com+2
  
• Why might this help? The authors suggest SIBO can increase gut permeability and send more inflammatory signals around the body, which may set off rosacea in people who are prone to it.
  
• Because rifaximin stays in the gut, the skin improvements are unlikely to be from a direct effect on the skin, which strengthens the gut–skin link in this group. owlstonemedical.com
  
• One interesting note: There’s a case report of rosacea settling when a patient’s gut transit time improved, hinting that motility may also matter. owlstonemedical.com

Why might SIBO make rosacea worse?

Researchers think several gut–skin pathways are at play:

1. Immune “cross-talk”
   When there is an overgrowth of bacteria in the small intestine, this excess quantity of bacteria will shed fragments (called endotoxins) that prime the immune system. This in turn will drives inflammation, flushing and new tiny blood vessels.
   
2. Leaky-gut and systemic messengers
   SIBO can increase intestinal permeability, letting irritants into the bloodstream that amplify skin redness. Reviews of the gut–skin axis support this mechanism. PMC
   
3. Vasoactive amines (e.g., histamine)
   Overgrowth of certain microbes raises histamine and other amines, which can trigger flushing and burning. (This is why some people notice alcohol, aged cheese or fermented foods worsen redness.) PubMed
   
4. Nerve–vessel sensitivity
   Gut-driven inflammation may sensitise the skin’s nerve and vessel “sensors” (TRP channels), so heat, spice or hot drinks trigger bigger flushes. PubMed
   

Get Tested for SIBO

If you have rosacea plus gut symptoms, it would be a good idea to test using a hydrogen/methane breath test.

If SIBO is present, you will need to treat the overgrowth, and continue your standard rosacea skin care)- combining both approaches often gives the best results. PubMed

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How do you treat SIBO?

Antibiotics

The usual first choice is rifaximin. If your breath test shows methane (constipation-type picture), doctors often combine rifaximin + neomycin. Rifaximin r it is not routinely prescribed by GPs and can be very expensive. Another good option is to use over the counter herbs.

Botanical (herbal) antimicrobials

We use a number of herbs in our clinic including berberine, oregano oil, neem, allicin/garlic extract and similar agents can be an alternative when antibiotics aren’t suitable or haven’t helped.

A comparative study found herbal therapy was at least as effective as rifaximin for normalising breath tests, and sometimes helped after rifaximin failed.

If you need help with rosacea and have been struggling to find a cause consider getting help.

Book a consultation today

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What is the best diet if you have rosacea and SIBO/IBS?

There’s no single “rosacea diet”, here are some options:

1) Low-FODMAP (short-term, dietitian-led) for IBS/SIBO-type symptoms

Low-FODMAP diets improvel IBS symptoms (pain, bloating, stool irregularity) and can make breath-test-positive patients more comfortable while you treat the root cause.

2) Mediterranean-style pattern for inflammation & skin health

Observational data suggest Mediterranean-like diets (vegetables, pulses as tolerated, whole grains, olive oil, oily fish, nuts) are associated with lower incident rosacea risk in non-overweight individuals and support systemic anti-inflammatory pathways.

3) Drink Coffee but avoid alcohol

• Caffeinated coffee (not scalding hot) is linked to a lower rosacea risk — feel free to keep your morning flat white or try iced coffee if heat triggers flushing. [3] JAMA Network
• Alcohol — particularly white wine and spirits — is associated with a higher rosacea risk; moderation or alternatives may help. [4] PubMed

4) What is a sample menu like?

• Breakfast: Lactose-free yoghurt with blueberries and chia; or eggs with grilled tomatoes and sourdough (or a low-FODMAP bread during restriction).
• Lunch: Grilled salmon, olive oil and lemon; quinoa or potatoes; rocket and cucumber salad.
• Dinner: Roast chicken, courgettes and carrots; small portion of rice; drizzle of extra-virgin olive oil.
• Snacks: Berries, almonds, walnuts, peppermint or ginger tea.
  
  

Read more about our approach to rosacea using functional medicine – We can provide functional medicine tests as well as providing detailed dietary and supplement advice.

Are there any other conditions linked to rosacea?

Rosacea often travels with other disorders — being aware helps you (and your clinician) manage you as a whole person.

• Gastrointestinal: Higher risks of IBS, IBD, coeliac disease, Helicobacter Pylori, and SIBO have been reported in studies. [6–7] PubMed+1
• Neurologic (migraine): In a Danish cohort, 12.1% of rosacea patients had migraine vs 7.3% of controls (adjusted HR 1.31). [31] PubMed
• Mental health: Meta-analyses and population data show higher rates of depression and anxiety in rosacea; screening and support are important. [32–33] PubMed+1

How rosacea itself is treated

These are some of the pharmaceuticals that may be used.

• Topicals: Ivermectin 1%, azelaic acid 15–20%, metronidazole for papules/pustules; brimonidine gel can reduce persistent erythema (vasoconstriction).
  
• Orals: Doxycycline (anti-inflammatory dosing) for papulopustular flares;
  
• Vascular lasers or IPL for telangiectasia/persistent erythema
  
• Sun protection is very important, cooler beverages, stress reduction, and alcohol moderation.

Key Takeaways:

1. Screen for SIBO if you have rosacea plus bloating, post-prandial distension, or IBS-type bowel changes.
   
2. Treat SIBO if present and support motility to prevent relapse.
   
3. Diet- A short-term low-FODMAP for symptom control, transitioning to a Mediterranean-style pattern long-term; keep drinking coffee (not too hot), go easy on white wine/spirits.
   
4. Treat the skin in parallel with evidence-based topicals/orals as needed
   

If you recognise yourself in this article — facial flushing or bumps plus digestive symptoms — book a SIBO breath test and consultation with our team.

We’ll build a tailored plan that coordinates gut treatment, skin-directed therapy, and dietary support so you can reduce flares and feel confident again.

FAQ

Is SIBO always the cause of rosacea?
No. Rosacea has several drivers (nerves/vessels, immune pathways, skin barrier, microbes on the skin, and personal triggers). SIBO looks important for a subset, especially when gut symptoms are present.

If my SIBO test is negative, could the gut still matter?
Possibly. Some people have rapid transit that complicates lactulose tests, and others may have upper-gut dysbiosis that isn’t captured.

How soon might skin improve after SIBO treatment?
In studies, some people improved within weeks; others took several months as gut motility and diet were optimised and skin treatments continued. Keep using your rosacea skincare/medical plan while you work on the gut.

Will I need a second round of treatment?
Sometimes. Relapse is more likely if motility is slow, there’s ongoing PPI use, or structural issues are present. Meal spacing and prokinetics can be helpful after eradication.

About the Author

Victoria Tyler a UK registered Nutritional Therapist and member of the British Association of Nutritional therapy. She was awarded UK BSc Honours Degree in Nutritional Therapy and has trained in GI Functional Medicine. Victoria has been working with Gut disorders since 2004 after first experiencing digestive problems herself. She felt that the NHS was unable to provide the support individuals needed and went on to specialise in this area before offering a bespoke IBS service.

Booking an appointment

If you need help with digestive symptoms please contact us and we would be pleased to book you in for a consultation at our IBS clinic

References

1. Parodi A, et al. Clin Gastroenterol Hepatol. 2008 — Higher SIBO in rosacea; rifaximin led to major skin improvement and durable remission in many.
2. Drago F, et al. J Am Acad Dermatol. 2016 — Follow-up note on rosacea tracking with SIBO recurrence.
3. Owlstone Medical. SIBO and Rosacea case-study summary — clear overview of design and outcomes.
4. Khurmatullina AR, et al. Ter Arkh. 2025 — Meta-analysis: SIBO more common in rosacea; improvement after eradication.
5. Rezaie A, et al. Am J Gastroenterol. 2017 — North American Consensus on hydrogen/methane breath testing (cut-offs and prep).
6. ACG Clinical Guideline: Small Intestinal Bacterial Overgrowth. Am J Gastroenterol. 2020 — Diagnostic and treatment guidance (rifaximin first-line; methane strategy).
7. Tansel A, et al. Clin Transl Gastroenterol. 2022 — Practical interpretation of breath tests.
8. Chedid V, et al. Glob Adv Health Med. 2014 — Herbal therapy non-inferior to rifaximin for normalising breath tests.
9. Early clinical data (2024) supporting botanical approaches; more robust trials still needed.