Pharmaceutical powders can be categorized as either simple or compound powders. The differences between them are outlined in the table below:
1) Preparation of Simple Powders
Simple powders consist of a single active ingredient, which may be combined with excipients. The steps involved in their preparation are:
A) Selection of Ingredients
Choose the active ingredient and any necessary excipients based on the desired therapeutic effect and dosage form.
Excipients may include diluents, lubricants, glidants, or flavoring agents.
B) Sizing of Ingredients
Ensure the active ingredient and excipients are of the appropriate particle size.
This may involve grinding, milling, or sieving to achieve the desired fineness.
C) Mixing
Combine the active ingredient and excipients in a suitable container.
For small batches, use a mortar and pestle or spatula. For larger batches, use mechanical mixers like tumble mixers, planetary mixers, or high-shear mixers.
D) Packaging
Package the prepared powder in appropriate containers to protect it from moisture, light, and contamination.
Packaging options include bulk containers, individual sachets, or unit-dose packets.
Preparation of Compound Powders
Compound powders contain two or more active ingredients combined in a single formulation.
The preparation steps are similar to simple powders but with additional considerations:
A) Selection of Ingredients
Select the active ingredients and any necessary excipients based on the desired therapeutic effect and dosage form.
Ensure the compatibility of the active ingredients to avoid drug-drug interactions or stability issues.
B. Sizing of Ingredients
Ensure that each active ingredient and excipient is of the correct particle size.
Each ingredient may need to be ground, milled, or sieved separately to obtain the appropriate fineness.
C) Mixing
Combine the active ingredients and excipients in a suitable container, mixing thoroughly for uniform distribution.
If ingredients vary significantly in quantity, use the geometric dilution technique:
Mix the smallest quantity ingredient with an equal amount of diluent.
Add this mixture to the next smallest ingredient and continue until all components are blended.
D) Packaging
Package the prepared compound powder in containers that protect it from moisture, light, and contamination.
Packaging options include bulk containers, individual sachets, or unit-dose packets.