One of the most common questions I get at the pharmacy counter is: “Should I take fibre or a probiotic for my gut?” The honest, evidence-based answer for most adults: both, together. Pairing a soluble fibre like psyllium husk with a clinically studied probiotic is called a synbiotic approach, and it consistently outperforms either supplement on its own for IBS, bloating and everyday digestive health.
This guide is the pairing protocol I use most often with patients: how SylliFlor and Alflorex work together, how to start, the timing details that matter, and what to expect week by week.
Key takeaways
- A synbiotic = prebiotic/soluble fibre + a clinically studied probiotic, taken together
- SylliFlor (psyllium husk) + Alflorex (the 35624 strain) is the pairing I most often recommend
- Take SylliFlor with breakfast in 250 ml water; Alflorex any time of day, with or without food
- Don’t take Alflorex in the same glass of water as SylliFlor — separate them by 2 hours to avoid the gel slowing capsule release
- Most patients see meaningful symptom change in 4–6 weeks; a full 12 weeks is a fair trial before deciding it isn’t working
What is a synbiotic?
A synbiotic is the combination of a prebiotic (a fibre or compound that feeds beneficial bacteria) and a probiotic (live beneficial bacteria themselves). The two are designed to work synergistically: the probiotic strain introduces or supports a beneficial species in your gut, and the prebiotic fibre helps it survive and thrive long enough to act on your symptoms.
Psyllium husk is a soluble, gel-forming fibre. While it’s not a classical prebiotic in the same way as inulin or FOS (which ferment rapidly and can worsen IBS bloating), it does support beneficial colonic bacteria — with a gentler fermentation profile that’s much better tolerated in IBS. That makes the SylliFlor + Alflorex pairing well suited to sensitive guts.
Why pair SylliFlor with Alflorex specifically?
Both products were chosen for this pairing for a reason. SylliFlor delivers a pure, palatable psyllium husk in a form patients will actually keep using day after day. Alflorex contains Bifidobacterium longum 35624 — the only Irish-developed probiotic strain with multiple randomised controlled trials in IBS specifically, originally developed at APC Microbiome Ireland in University College Cork.
The pairing rationale:
- Different mechanisms — psyllium acts in the lumen of the bowel (mechanically softening and bulking stool, slowing transit when needed, speeding it when needed). Alflorex acts on the gut microbiome and the gut’s inflammatory signalling. The two complement each other; they don’t overlap.
- Different timelines — psyllium tends to deliver stool form benefits within 1–2 weeks. Alflorex usually needs 4 weeks to show its effect on pain and bloating. Patients see a steady, layered improvement rather than waiting for one thing to work.
- Excellent tolerance profile — unlike the FODMAP-rich prebiotics found in many other gut supplements, this pairing is well tolerated by the majority of IBS patients.
SylliFlor + Alflorex — The Pharmacist’s Pairing
Roisin’s most-recommended starter combination. Start with SylliFlor Plain or your preferred flavour, and Alflorex Precision Biotics 30 capsules for the first month.
How to take them together — timing and dosing
The single most important rule: don’t take Alflorex in the same glass of water as SylliFlor. Psyllium forms a gel that can delay capsule disintegration, which may reduce the probiotic’s effectiveness. The fix is simple — separate them by at least 2 hours.
The routine I recommend:
| Time | What to take | How |
|---|---|---|
| Breakfast | SylliFlor (1 tsp) | Stirred into 250 ml water or juice. Drink immediately. |
| Mid-morning | Alflorex (1 capsule) | Any time, with or without food. With water. |
| Evening (optional) | SylliFlor (1 tsp) | After week 2, add a second daily teaspoon at dinner. |
If you find a morning routine easier to remember, taking Alflorex with breakfast and SylliFlor mid-morning works equally well. The order doesn’t matter — the 2-hour separation does.
What to expect, week by week
Your first 8 weeks on SylliFlor + Alflorex
- Week 1: Some patients notice transient bloating or wind as the gut adjusts to the added fibre. This usually settles within 5–7 days. Drink plenty of water throughout the day.
- Week 2: Stool form usually starts to normalise — softer if you tend toward constipation, more formed if you tend toward loose stools. Don’t increase the dose yet.
- Weeks 3–4: Increase SylliFlor to two teaspoons daily (one with breakfast, one with dinner). The Alflorex strain should be reaching steady-state in the colon now — pain and bloating typically begin to ease.
- Weeks 5–6: The bulk of the improvement most patients will feel happens in this window. Keep a brief symptom diary so you can judge fairly.
- Weeks 7–8: Review. If you’ve had at least 30% symptom improvement, you’re on the right track — stay on the maintenance dose. If not, this is the point to add Colpermin (peppermint oil) on flare days, or consider a structured low-FODMAP trial under a dietitian.
Pairing recommendations by IBS subtype
| If your IBS is… | SylliFlor | Alflorex |
|---|---|---|
| IBS-C (constipation) | Start 1 tsp daily, build to 2 tsp daily over 2 weeks | 1 capsule daily for 4+ weeks |
| IBS-D (diarrhoea) | Start ½ tsp daily, build very slowly to 1 tsp daily over 3–4 weeks | 1 capsule daily for 4+ weeks |
| IBS-M (mixed) | 1 tsp daily, increase only if tolerated | 1 capsule daily for 4+ weeks |
Simplifying the routine — Alflorex Dual Action
If you’d prefer a single-capsule option that combines the Alflorex probiotic strain with added fibre, Alflorex Dual Action is worth considering. It won’t replace the bulk-forming benefits of a full SylliFlor dose, but for patients who travel a lot, struggle with routine compliance, or want to start with one daily capsule rather than two products, it’s a sensible stepping stone.
Alflorex Dual Action Probiotic & Fibre
The 35624 Alflorex strain combined with soluble fibre in a single daily capsule. Good for travel, simplicity or as a maintenance option after a SylliFlor + Alflorex starter course.
Shop Dual Action →For long-term maintenance — the 3 Month Alflorex Supply
Patients who’ve completed an initial 4-week trial of Alflorex and want to stay on it for ongoing benefit get much better value from the 3-month pack. The strain needs continuous daily dosing to maintain its presence in the gut — it doesn’t colonise long-term once you stop.
Alflorex 3 Month Supply
90 capsules — the most cost-effective option for ongoing maintenance dosing once you’ve confirmed Alflorex works for you.
Shop 3 Month Supply →Common pairing mistakes to avoid
- Taking SylliFlor and Alflorex in the same glass — the psyllium gel can delay capsule release. Separate them by 2 hours.
- Loading psyllium too fast — going from zero to 3 tablespoons a day in week one guarantees bloating. Build up over 2–3 weeks.
- Stopping Alflorex at 2 weeks — the strain needs a full 4 weeks to show its effect. Don’t judge it early.
- Stopping Alflorex once you feel better — it doesn’t colonise long-term. The benefit lasts only as long as the daily dose continues.
- Not drinking enough water — psyllium needs at least 250 ml per teaspoon. Drink it immediately after mixing, before it thickens.
Frequently asked questions
Can I take SylliFlor and Alflorex at the same time?
Not in the same glass of water — separate them by at least 2 hours. Psyllium’s gel can delay the Alflorex capsule from releasing properly. Taking SylliFlor with breakfast and Alflorex mid-morning works well for most patients.
How long should I trial this pairing before deciding if it works?
Give it a full 8–12 weeks. Stool form usually improves in the first 1–2 weeks; pain and bloating improvements typically build between weeks 3 and 6.
Is this pairing safe in pregnancy or breastfeeding?
Both psyllium husk and Alflorex have favourable safety profiles, but I always recommend pregnant or breastfeeding patients confirm any new supplement with their GP, midwife or pharmacist before starting.
Can I take this pairing alongside my prescription medication?
Psyllium can slow the absorption of some medications if taken within 1–2 hours of a dose — separate it from your medication by 2 hours either side. Alflorex has no significant medication interactions, but always speak to your pharmacist if you’re on multiple prescriptions.
What if SylliFlor + Alflorex isn’t enough?
If you’ve completed 8 weeks with limited improvement, the next steps are typically: add Colpermin (peppermint oil) on flare days, start a structured low-FODMAP elimination trial with a registered dietitian, and review with your GP if symptoms persist.
Do I need both, or can I just take Alflorex Dual Action?
Alflorex Dual Action is a good simplified option, but it doesn’t deliver a full bulk-forming psyllium dose. For patients with constipation-predominant IBS, or anyone who needs the stool-bulking effect of a full psyllium dose, the separate SylliFlor + Alflorex pairing works better.
About the author
Roisin Cahill MPharm MPSI is a PSI-registered pharmacist (Reg. 11957), Trinity College Dublin MPharm graduate and Co-Founder of RoCa Healthcare. She is Chemco Pharmacy’s gut health and IBS specialist and co-developer of the SylliFlor® psyllium husk range.
→ Read Roisin’s full pharmacist profile