For total versatility in design and development of tablet formulation a quality enhancing cost effective diluent for solid dosage forms.


    1.  Nontoxic, Chemically & Physiologically inert.
    2.  Physically & Chemically stable both by itself and in combination with the drug.
    3.  Free of unacceptable microbes & does not support mould growth.
    4.  Colour compatible and maintains the uniformity of shades.
    5.  Has no deleterious effect on the bioavailability of active drug.


Product Specification:

Physical Analysis



Physical form

A fine, odourless, tasteless, amorphous powder



Effect of heat

Looses 1½H2O at 128ºC & 2H2O at 163ºC

Chemical Analysis

Identification Test – USP-NF


Loss on Drying – USP-NF


Iron – USP-NF


Heavy Metals – USP-NF


Assay – USP-NF

98% - 101%

Foreign Particles – In house


Chloride – In house


pH – In house

Neutral to litmus

Microbiological Analysis

Total viable Aerobic Count

NMT 10 / g


NMT 10 / g

Total Coliform, Salmonella, Staphylococcus aureus,
Pseudomonas aeruginosa

Absent in 10 g

Comparative Practical Observation

Quality Calpax Lactose DCP
Effect on D.T. Best Good Better
Surface Finish Best Best Poor
Friability Low Lowest High
Wear-Tear of Die-Sets Low Minimum High
Colour Distribution Best Good Poor
Setting effects during
shelf life
Least Highest High
Effect on appearance
during shelf life
No change May turn brownish
(Haillard Reaction)
Turns off-white
Probability of microbial contamination Minimum Fair Maximum
Acceptability to diabetic patient Most Minimum Fair
Cost Least Most fair


Products Grades Available:

Calpax® Powder: A fine powder for wet granulation. It can be used upto 75% or three-fourth of the total diluent portion in combination with starch maintaining disintegration time to the minimum.

Calpax® - D.C.: (Direct compressible granules of desired size) - whenever direct compression is feasible, readymade granules of the diluents are required. Calpax-D.C. is ideal form for immediate use. When size/weight of a tablet is needed to be increased, Calpax dummy granules are very handy. Calpax-D.C. does not require any other excipient except disintegrating and lubricating agents.

Calpax® - C (Capsule grade free flow granular powder)-Capsule filled on semi-automatic or automatic machines need flowability of the bulk material. Calpax-C serves the purpose. Calpax-C increases the flow of the material thereby filling is faster & uniform resulting in enhanced production.

Calpax® - ST: This is especially introduced for Steroids like Dexa / Beta - methasone and Prednisolone etc.

Calpax® - VET: This is a fine powder which is used in FEED - FORMULATIONS through wet process or as fillers in powders. It is widely used as Calcium Suppliment.


Direct Compression

For direct compression, Calpax DC (Directly Compressible), grade of CALPAX is used.

In this process, active ingredients and excipients (D.C. form) are blended and compressed directly. It is the most widely accepted, less elaborate, most economical way of production.

Advantages of Direct Compression are as under:

  • Reduced investment
  • Reduced production cost
  • Reduced friability
  • Reduces time
  • Saves energy due to elimination of heat and moisture and simpler production steps, thus stability in the final product.


    Calpax is diluent of the right choice for solid dosage forms. It offers total versatility in design and development of tablet formulation and affords protection from mould & microbes.