Specialty Minerals Precipitated Calcium Carbonates In Pharmaceuticals


In pharmaceutical applications, the most common use of calcium carbonate is the active ingredient in calcium-based antacids. Calcium carbonate is a rapid and effective acid neutralizer that is also economical to use.  Calcium-based antacids come in a broad range of forms: tablets, liquids, soft chews, soft gels, effervescents and chewing gums. You can click on the link below to read more about formulating for this antacid application with Specialty Minerals Precipitated Calcium Carbonates (PCCs).

Other pharmaceutical applications depend on calcium carbonate’s acid neutralization power, its high calcium content—40 percent elemental calcium—its absorptive power, especially in the form of a high surface area particle, as well as on its ability to act as a less expensive filler and extender.

Antibiotic Manufacture
During fermentation of antibiotics, precipitated calcium carbonate is added to help control and buffer the pH of the broth. When fermentation is complete, PCC is added as a flocculant, to help clarification and filtration. A high surface area grade is normally used to provide the maximum area for absorption and for rapid reaction. The scalenohedral, pharmaceutical-grade PCCs suggested are: ViCALity® Extra Light PCC, made in the U.S. or Calopake® Extra Light PCC, made in the U.K. They are 2 to 3 microns in particle size. From this scanning electron micrograph of Extra Light, made at 10,000 times magnification, you can see how the scalenohedral, or starburst-type, morphology gives the desired high surface area. Another high surface area grade, Sturcal™ L PCC is also manufactured in the U.K.


There may be applications where a technical grade is acceptable during processing. The same high surface area scalenohedral shaped PCCs come in high purity, uncertified technical grades. They are: Albacar® 5970, in the U.S. and Calopake® 5970 in the U.K.

Calcium-Based Pharmaceutical Raw Materials
High-purity Specialty Minerals PCCs are also used as a raw material in pharmaceutical manufacture, either to make a calcium salt for use as a nutritional supplement or for food fortification, such as calcium citrate, lactate or ascorbate, or can be reacted into a new drug as an essential moiety.

Often used are either one of the 2 to 3 micron scalenohedral particles, shown above, or a small solid particle with a moderately high surface area, such as ViCALity Albafil® PCC or CalEssence® 70 PCC, seen here:

Along with choice of particle size and shape, the chemist may also have to consider lead levels. If the calcium compound is used in an application in the United States, and if the daily dosage is high, the product might be required to meet the lead limits under California Proposition 65. For this situation, you can choose one of the CalEssence® PCCs, which have a lead specification of less than 125 ppb, or the ViCALity® PCCs, which have less than 500 ppb lead. The scalenohedral PCCs are CalEssence® 160, and ViCALity® Extra Light PCCs, and the small, solid PCCs are CalEssence® 70 and ViCALity Albafil® PCCs.

Buffered aspirin and other buffered tablets
The acid neutralizing capacity of calcium carbonate is also utilized in the manufacture of buffered aspirin and other pharmaceuticals, where the low pH of the main active ingredient may cause stomach distress. The inclusion of some calcium carbonate in the tablet helps buffer, or stabilize, the mixture at a higher pH, so the drug is easier on the stomach. Follow the product recommendations for the dosage form of the product being made, using one of the links below.

Tablet excipient and filler
Calcium carbonates are also cost-effective excipients and fillers for tablets, especially when compounding hygroscopic ingredients that tend to clump or become sticky when they absorb moisture—aspirin, vitamin C, and others. When used for tableting, calcium carbonate must first be granulated; it cannot be directly compressed. Click on the granulating link below to read more about granulating calcium carbonates, and on the PCCs recommended for tablets.


Regulatory Compliance
The Adams, Massachusetts and Birmingham, England plants of Specialty Minerals, where these pharmaceutical grade products are manufactured, are registered with the U.S. Food and Drug Administration (FDA) as Drug Manufacturing Facilities. Good Manufacturing Practices (GMP) are followed carefully. The ViCALity® and CalEssence® PCC families made in Adams are certified as meeting the U.S. Pharmacopeia and the Food Chemicals Codex. The Calopake® and Sturcal™ PCC families made in Birmingham are certified as meeting European Pharmacopeia (EP), British Pharmacopeia (BP), and the EU Miscellaneous Food Regulations E170i. These UK products can also be certified as USP / FCC, on request. All products are also certified as Kosher. Each plant has been ISO 9000 quality certified.