Medicines & Supplements A to Z > Alginate


Last updated on July 29, 2019.

Overview   |   Dosage   |   Side Effects   |   Where To Buy  

GENERIC NAMES: Alginate, Alginic acid, Sodium alginate



What is Alginate for?

Alginate is a substance usually used with other antacids (e.g. Calcium Carbonate) for treating dyspepsia and heartburn. When it contacts with the acid in your stomach, it forms a gel over the wall of your stomach which acts as a barrier to prevent acid reflux.

How to use it?

Alginate is usually combined with sodium or potassium bicarbonate and calcium carbonate. It is taken by the mouth either in chewable tablets or liquids. The usual doses for different products are listed as follows:

Gaviscon Chewable Tablet

Adults/ Child ( 12 years)

2-4 tablets after meals and before bedtime

Gaviscon Extra Stength 500 Chewable Tablet

Adults/ Child ( 12 years)

1-2 tablets after meals and before bedtime

Gaviscon Double Action Chewable Tablet

2-4 tablets after meals and before bedtime, up to 4 times daily

Gaviscon Liquid

Adults/ Child ( 12 years)

10-20 mL after meals and before bedtime

Gaviscon Advanced Liquid

Adults/ Child ( 12 years)

5-10 mL after meals and before bedtime

How to use it?

As a medicinal product, Activated Charcoal can be either taken in conventional tablets or suspension. If you are taking a suspension form of Activated Charcoal, you can mix it with flavouring agents like coke or juices to make it more palatable. 

When used for indigestion or intestinal gas, the suggested adult dose of Activated Charcoal tablets is 2-4 tablets by mouth 3 times per day.

What are the side effects of Alginate?

Common side effects of Alginate can include water retention, nausea and vomiting and flatulence. People with high blood pressure or heart failure may need to avoid products containing Alginate as they often have a high sodium content.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

For detailed information about the use of Alginate in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.