Our precipitated calcium carbonates are excellent active pharmaceutical ingredients for antacids designed to reduce excess stomach and gastric acid.

Calcium carbonate to relieve gastric acid complaints

Our pharmaceutical-grade precipitated calcium carbonates contain alkaline ions that render stomach acid more neutral and counteract symptoms linked to excess stomach acids, such as acid reflux, heartburn and indigestion.

Highly soluble, our calcium carbonates contain alkaline ions that chemically neutralize gastric acid, reducing damage and relieving pain.

We recommend our Calcius™ range for antacids

Our Calcius range is suitable as an active pharmaceutical ingredient in swallowable, effervescent and chewable antacid products as well as antacids in powder form.


Our pharmaceutical-grade precipitated calcium carbonates, including the Calcius range:

  • Comply with US Pharmacopeia
  • Comply with EU Pharmacopeia
  • Are manufactured, processed and packaged in compliance with cGMP (Good Manufacturing Practices) at ISO 9001:2015 and HACCP certified facilities
  • Are certified halal and kosher
  • Eligible for vegan certification 
  • EINECS no. 207-439-9
  • CAS no. 471-34-1

IPEC member

As an IPEC member, Imerys guarantees the safety, quality and consistency of its pharmaceutical grades, which are all derived from controlled, proprietary sources, and are available for audit. 

The Pharmaceuticals Regulatory Package and Kosher certificate are available from our download center.