Sodium Alginate

Alginate Compare

Find the cheapest raft-forming antacid available in the US — sorted by cost per dose.

What is sodium alginate? It's a seaweed-derived ingredient that forms a floating gel "raft" on top of stomach contents when it contacts acid — physically blocking reflux rather than just neutralizing it. It works differently from calcium carbonate or proton pump inhibitors.

Why isn't this at CVS? The Gaviscon sold in US pharmacies uses aluminum and magnesium hydroxide — not sodium alginate. The UK formulation does. The products below are US-made sodium alginate brands and UK Gaviscon imports available on Amazon.

8 products

Product↕	Form	Per dose	Store & size	Price	$/dose↑	Buy
Reflux Gourmet US	liquid 5 ml / 1 tsp	425mg alginate 28mg sodium	Reflux Gourmet 8 oz · 47 doses	$28.00 as of Oct 24, 4:19 PM PT	$0.60 Best value 8 oz	Reflux Gourmet ↗
			Reflux Gourmet 25 single-serve packs · 25 doses	$34.00 as of Oct 24, 4:19 PM PT	$1.36 25 single-serve packs	Reflux Gourmet ↗
			Amazon 8 oz · 47 doses	—	See price on Amazon 8 oz	Amazon →
			Amazon 25 single-serve packs · 25 doses	—	See price on Amazon 25 single-serve packs	Amazon →
Gaviscon Advance Liquid ("Gav") UK import Weird: On Amazon this is available but they are hiding the Gaviscon name and the bottle design looks like medical supply and not retail	liquid 5 ml / 1 tsp	500mg alginate 58mg sodium	British Essentials 250 ml · 50 doses	$33.99 as of Oct 24, 4:19 PM PT	$0.68 250 ml	British Essentials ↗
			Amazon 500 ml · 100 doses	—	See price on Amazon 500 ml	Amazon →
			Amazon 500 ml × 2 · 200 doses	—	See price on Amazon 500 ml × 2	Amazon →
Reflux Raft US Discount with subscription	liquid 5 ml / 1 tsp	338mg alginate 28mg sodium	Reflux Raft 8 oz · 47 doses	$32.99 as of Oct 24, 4:19 PM PT	$0.70 8 oz	Reflux Raft ↗
Reflux Raft US Discount with subscription	liquid 5 ml / 1 tsp	338mg alginate 28mg sodium	Amazon 8 oz · 47 doses	—	See price on Amazon 8 oz	Amazon →
Refluxter US	tablet 2 capsules	1000mg alginate 150mg sodium	Nutritist 60 capsules · 30 doses	$32.99 as of Oct 24, 4:19 PM PT	$1.10 60 capsules	Nutritist ↗
Refluxter US	tablet 2 capsules	1000mg alginate 150mg sodium	Amazon 60 capsules · 30 doses	—	See price on Amazon 60 capsules	Amazon →
Gaviscon Double Action Liquid UK import Pink bottle	liquid 10 ml / 2 tsp	500mg alginate 127mg sodium	British Essentials 500 ml · 50 doses	$61.79 as of Oct 24, 4:19 PM PT	$1.24 500 ml	British Essentials ↗
Gaviscon Double Action Liquid UK import Pink bottle	liquid 10 ml / 2 tsp	500mg alginate 127mg sodium	Amazon 150 ml × 2 · 30 doses	—	See price on Amazon 150 ml × 2	Amazon →
HartSpan Khelp US Newest on market?	tablet 2 capsules	950mg alginate 190mg sodium	HartSpan 60 capsules (monthly subscription) · 30 doses	$46.00 as of Oct 24, 4:19 PM PT	$1.53 60 capsules (monthly subscription)	HartSpan ↗
			HartSpan 60 capsules · 30 doses	$54.00 as of Oct 24, 4:19 PM PT	$1.80 60 capsules	HartSpan ↗
			Amazon 60 capsules · 30 doses	—	See price on Amazon 60 capsules	Amazon →
Gaviscon Advance Chewable UK import These get really gummy when chewing	tablet 1 tablet	500mg alginate 53mg sodium	Amazon 120 tablets (2 × 60) · 120 doses	—	See price on Amazon 120 tablets (2 × 60)	Amazon →
Gaviscon Double Action Tablets UK import	tablet 2 tablets	500mg alginate 106mg sodium	Amazon 24 tablets · 12 doses	—	See price on Amazon 24 tablets	Amazon →

Research & Resources

Articles, links, and resources on sodium alginate and acid reflux.

1 items

External ↗

Research: Gaviscon Double Action alginate-antacid combo worked best

A 2017 study comparing alginate antacid products head-to-head found that not all alginate formulas work equally well — the quality of the formula matters as much as the amount of alginate. Gaviscon Double Action came out on top (note: the study was funded by its maker, Reckitt Benckiser).

Aug 17, 2017