Alginic acid

Generic Medicine Info
Indications and Dosage
Gastro-oesophageal reflux disease
Adult: As chewable tab containing 150 mg alginic acid, 625 mg Ca carbonate, and 73.50 mg heavy Mg carbonate: Chew 2 tabs preferably 1 hour after meals and before bedtime. Max duration: 14 days. As chewable tab containing 200 mg alginic acid, 30 mg dried Al hydroxide gel, and 40 mg light Mg carbonate: Chew 1-3 tab(s) after meals and at bedtime, or as prescribed. Max duration: 14 days. Seek medical advice if symptoms persist after 14 days.
Child: >12 years As chewable tab containing 150 mg alginic acid, 625 mg Ca carbonate, and 73.50 mg heavy Mg carbonate: Same as adult dose.
Intestinal obstruction. Chewable tab containing alginic acid, Ca carbonate, and heavy Mg carbonate: Hypercalcaemia or conditions resulting in hypercalcaemia; hypercalciuria, nephrolithiasis (due to calculi-containing Ca deposits), pre-existing hypophosphataemia. Severe renal impairment.
Special Precautions
Patient with fluid retention. Chewable tab containing alginic acid, Ca carbonate, and heavy Mg carbonate: Patient with constipation, haemorrhoids, sarcoidosis. Not indicated for long-term treatment. Renal impairment. Children. Pregnancy and lactation.
Adverse Reactions
Significant: Chewable tab containing alginic acid, Ca carbonate, and heavy Mg carbonate: Hypercalcaemia, hypermagnesaemia, milk alkali syndrome, and increased renal calculi formation (prolonged use); masking of stomach malignancy.
Gastrointestinal disorders: Constipation, nausea, vomiting, abdominal distension, diarrhoea, hiccup.
Immune system disorders: Rarely, hypersensitivity reactions.
Musculoskeletal and connective tissue disorders: Muscle weakness.
Monitoring Parameters
Monitor Ca, phosphate and Mg levels in patients with renal impairment.
Drug Interactions
May hinder the absorption of tetracyclines, quinolones, bisphosphonates, levothyroxine, dolutegravir, eltrombopag, cardiac glycosides (e.g. digoxin, digitoxin).
Description: Alginic acid reacts with the gastric acid to form a viscous gel or “raft” that floats on the surface of stomach contents. This activity acts as a mechanical barrier to reduce reflux or protect the oesophageal mucosa during reflux. Usually combined antacids such as Ca carbonate, Mg carbonate, and Al hydroxide works synergistically with alginic acid by neutralising the excess acid in the stomach.
Absorption: Not converted in the gastrointestinal tract.
Chemical Structure

Chemical Structure Image
Alginic acid

Source: National Center for Biotechnology Information. PubChem Database. Alginic acid, CID=6850754, (accessed on June 29, 2020)

Store below 30°C. Protect from moisture and direct sunlight.
MIMS Class
Antacids, Antireflux Agents & Antiulcerants
ATC Classification
A02BX13 - alginic acid ; Belongs to the class of other drugs used in the treatment of peptic ulcer and gastro-oesophageal reflux disease (GERD).
Algycon Chewable Tablets (American Taiwan Biopharm Co., Ltd.). MIMS Thailand. Accessed 11/06/2020.

Buckingham R (ed). Alginic Acid. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. Accessed 11/06/2020.

Dyspepsia and Peptic Ulcer Disease. Gold Standard Drug Database in ClinicalKey [online]. Elsevier Inc. Accessed 11/06/2020.

Joint Formulary Committee. Alginic Acid. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. Accessed 11/06/2020.

Rennie Extra Tablets; Rennie Dual Action Chewable Tablets (Bayer plc). MHRA. Accessed 11/06/2020.

Disclaimer: This information is independently developed by MIMS based on Alginic acid from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Sign up for free
Already a member? Sign in