Refluxter vs. Gaviscon Advance: An Expert Comparison of Alginate-Based Reflux Support
Medically reviewed by Sarv Kannapiran M.D., J.D., M.B.A— Written by Helena Vargas Cabeda
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Last updated: November 20, 2025
Medically reviewed by Sarv Kannapiran, M.D.
Category: Alginate Science, GERD, LPR
Overview
Alginate therapy is one of the most evidence-backed, non-systemic ways to support people dealing with heartburn, acid reflux, GERD, and laryngopharyngeal reflux (LPR). Instead of changing how much acid the stomach makes, alginates form a physical “raft” that floats on top of stomach contents and helps block reflux at its source.
Two of the most-discussed alginate-based options are:
- Gaviscon Advance – an over-the-counter (OTC) liquid medicine (drug) with a high sodium alginate content.
- Refluxter – a dietary supplement focused on delivering a high alginate dose in clean-label capsules, without aluminum, preservatives, or artificial sweeteners.
Both products rely on the same core mechanism of sodium alginate raft formation, and both use sodium alginate sourced from high G-block origin seaweed, chosen for robust gel and raft formation. However, they differ in format, excipients, and how people typically use them. This article breaks down those differences in clear, unbiased, expert-level detail.
1. The Science of Alginate Raft Formation
Alginate is a natural polysaccharide derived from brown seaweed. When it enters the stomach and encounters acid, it forms a thick gel. That gel can trap gas and float on top of stomach contents, creating what’s known as a raft. This raft:
- Floats to the top of the stomach contents, near the gastroesophageal junction.
- Helps “cap” the post-meal acid pocket.
- Creates a physical barrier between the stomach contents and the esophagus.
- Reduces exposure of the esophagus to acid, pepsin, and bile.
The key point: alginate products work through physics, not systemic pharmacology. They do not need to enter the bloodstream or shut down acid production to provide benefits. The strength and stability of this raft depends largely on how much alginate is present and the gel-forming characteristics of the alginate, which are strongly influenced by a high proportion of G-block (guluronic-acid–rich) regions in the alginate chain.
Both Refluxter and Gaviscon Advance use sodium alginate from high G-block origin seaweed specifically selected to support firm, stable raft formation under gastric conditions.
2. Alginate Concentration: How Much Alginate Per Dose?
Gaviscon Advance (UK Formulation)
- Each 10 mL oral dose contains 1000 mg sodium alginate and 200 mg potassium hydrogen carbonate.
- Liquid suspension taken after meals and at bedtime.
Refluxter
- Each 2-capsule serving delivers a high-dose alginate complex with sodium alginate as the primary functional ingredient. The amount of sodium alginate in the complex is 1,100+ mg, the highest amount per serving available in the United States.
- Capsules are designed for use after meals with water.
- Formulated without aluminum, artificial sweeteners, or preservatives.
In both products, sodium alginate is the star of the show. Higher alginate doses generally correlate with stronger, more stable rafts. That’s why alginate content is often the single most important variable when scientists compare raft-forming products.
3. G-Block Content and Raft Strength
Not all alginates are identical. They are made of two building blocks: G-blocks (guluronic acid–rich regions) and M-blocks (mannuronic acid–rich regions). Alginates with a higher proportion of G-blocks tend to form:
- Stronger gels
- More cohesive rafts
- Better mechanical stability under gastric conditions
Both Refluxter and Gaviscon Advance use sodium alginate derived from seaweed sources that are known for high G-block content. This high G-block profile supports the formation of firm, stable rafts when the alginate is exposed to stomach acid and ions.
In practical terms, both products rely on the same principle: a strong, buoyant alginate gel that can cap the acid pocket and help reduce post-meal reflux events.
4. Capsules vs. Liquid: Delivery Format Matters
Gaviscon Advance (Liquid)
- Forms a raft almost immediately in the stomach.
- Often used for rapid, on-the-spot symptom relief.
- Contains sweeteners, flavorings, and preservatives to make the product palatable and shelf-stable.
- Mint or aniseed flavors are standard in many markets.
Refluxter (Capsules)
- Capsules dissolve in the stomach within minutes after swallowing.
- Designed for use after meals to support raft formation when the stomach is full.
- No flavors, sweeteners, or preservatives. Thus, suitable for people who avoid unnecessary additives.
- Portable, neutral-tasting, and easy to incorporate into daily routines or travel.
For some people, the liquid texture and taste of antacid-style products are a dealbreaker. For others, a familiar, medicinal liquid is exactly what they prefer. Capsules like Refluxter can improve long-term adherence in people who want high alginate intake without dealing with taste or texture issues.
5. Additives, Sweeteners, and “Clean Label” Considerations
| Feature | Gaviscon Advance (Liquid) | Refluxter (Capsules) |
|---|---|---|
| Product category | OTC medicine (drug) | Dietary supplement |
| Sweeteners | Yes (e.g., saccharin, sorbitol in some versions) | No |
| Preservatives | Yes (e.g., parabens in some formulations) | No |
| Aluminum | None in the UK Advance formulation | None |
| Flavorings | Mint or aniseed flavors | None |
| Form | Thick liquid suspension | Swallowable capsules |
People who are sensitive to mint, sweeteners, or preservatives, or those following a very “clean label” lifestyle often prefer an additive-minimal product like Refluxter. Others prioritize the medicinal familiarity and taste-masking of a flavored, ready-to-drink liquid such as Gaviscon Advance.
6. Typical Use Cases: When Each Product May Make Sense
Gaviscon Advance May Be a Good Fit If:
- You want a drug-class OTC product with a long history of use.
- You prefer a liquid that feels soothing as you swallow it.
- You are looking for rapid, on-the-spot symptom relief after meals or at bedtime.
- You don’t mind mint/aniseed flavor or sweeteners.
Refluxter May Be a Good Fit If:
- You want a high alginate dose in a simple, capsule format.
- You care about a clean-label formula with no preservatives, sweeteners, or flavorings.
- You are sensitive to mint, sorbitol, or liquid antacids.
- You prefer a supplement-style approach that supports physical raft formation without additional antacids.
- You want something discreet and travel-friendly that you can keep in a bag, desk, or carry-on, including without any problems at the airport security.
Both products are intended for adults. Anyone with underlying medical conditions, on medications, or who is pregnant or breastfeeding should talk to a healthcare professional before using either product.
7. Safety and Side-Effect Profile
Alginate-based products are generally well tolerated. Because they primarily act in the stomach and esophagus, they have minimal systemic absorption. However, the excipients and sodium load can matter for some individuals.
Gaviscon Advance
- Contains sodium and potassium. This is relevant for people on salt-restricted diets or with certain kidney or heart conditions.
- Contains sweeteners and preservatives, which may cause GI upset or sensitivity in some users.
- As a medicine, it has formal prescribing information, contraindications, and drug interaction warnings that patients should review with a healthcare professional.
Refluxter
- Focused on alginate as the primary functional ingredient, with a short and transparent excipient list.
- Free from aluminum, potassium, artificial sweeteners, and preservatives.
- Intended for adults as a dietary supplement; users should follow the label directions and consult their clinician if they have medical conditions or take other medications.
As with any product that affects the upper GI tract, people should discontinue use and seek medical advice if they experience concerning or persistent symptoms.
8. Evidence Base for Alginate Therapy (Big Picture)
Most of the formal clinical research has been performed on pharmaceutical alginate formulations similar to Gaviscon-type products. These studies consistently show that:
- Alginate formulations can reduce reflux events by forming a physical barrier at the top of the stomach contents.
- They can be more effective than simple antacids for symptomatic relief in many patients.
- They work through a mechanical mechanism rather than suppressing acid production.
Refluxter is built on the same raft-formation principle, using high-quality sodium alginate from high G-block origin seaweed in a supplement format. While Refluxter itself is not a drug and is not approved to diagnose, treat, cure, or prevent any disease, it leverages the same fundamental chemistry that has been extensively studied in alginate-based reflux therapies.
9. Summary: Which Is “Better” – Refluxter or Gaviscon Advance?
There is no one-size-fits-all answer. Both products rely on the same core mechanism of alginate raft formation using sodium alginate from high G-block origin seaweed, but are optimized for different user preferences and regulatory categories.
- If you want a classic OTC liquid medicine with a long clinical track record and rapid soothing action, Gaviscon Advance is the better fit.
- If you want a high-alginate, clean-label capsule with no sweeteners, preservatives, or flavors, and a simple ingredient profile, Refluxter is likely a better match for your preferences.
From a purely mechanistic standpoint, total alginate content, G-block–rich structure, and raft strength are the big drivers of performance. Refluxter is formulated to deliver a substantial alginate dose (4x-8x more that US based gel products) in a capsule format, while Gaviscon Advance delivers a similarly high alginate dose in a flavored liquid suspension with added antacid components.
Important: Refluxter is a dietary supplement, not a drug. It is not intended to diagnose, treat, cure, or prevent any disease. Always work with your healthcare provider to evaluate persistent reflux, GERD, or LPR symptoms and to determine which therapy approach is appropriate for you.
Additional information is available on the Refluxter product page.
Disclaimer: This article is not intended to provide medical advice. It is for informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. The statements here have not been evaluated by the Food and Drug Administration. Refluxter is not intended to diagnose, treat, cure, or prevent any disease. Please consult your physician for medical guidance.
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