Simple & Compound Powders– Official Preparations

The powdered form of a drug or chemical consists of finely divided components in dry form. Powders can be applied internally and externally. Powders can be either crystalline-like or amorphous. It is believed that the particle size of powder and dissolution, absorption, and therapeutic effect of drugs are correlated.

Advantages
The stability of powder dosage forms is greater than that of liquid dosage forms. Liquid dosage form has a lower chance of incompatibility compared to liquid medication. Powdered forms of the drug are more rapidly acting as compared to other solid forms of the drug, such as tablets and capsules. In body fluids, powder dissolves easily because of its smaller particle size. Dissolving or mixing powdered drugs in appropriate liquids enables the patient to consume a greater quantity of the medicine orally. Whether dispersed in water or any other liquid, powdered drugs are easy to take my small children or elderly patients. A powder dosage form is more economical than other forms of dosage because no specialized machines or techniques are needed. Liquid dosage forms are heavier and more difficult to transport than powders.

Disadvantage
It is impossible to dispense powdered medications that have bitter, nauseous, or unpleasant tastes. The powder form of deliquescent and hygroscopic drugs is not permitted. The powder form of some drugs is not suitable for dispensing because they are affected by atmospheric conditions. The process of dispensing powder is very lengthy.

Internally administered powders, simple & compound
Individual doses of powder are enclosed in a paper in this form. A compound powder has more than one ingredient, such as simple powder but less than one is simple powder. To make powders easily handled by patients and weighed accurately, the minimum quantity of each powder should not be less than 100 mg.

Simple powders

There are generally only one or two ingredients in a powder, either crystallized or amorphous. The powder may be present in crystalline form, in which case it is crushed to a fine powder, measured, divided into portions, and packaged individually.

Example - Dispatched six aspirin powders, each containing 300 mg of aspirin

Rx, aspirin 300mg

Procedure - Prepare the aspirin by powdering it & weighing the required amount. Individually wrapped powder paper is used to weigh and package aspirin powder. There is 300 mg of aspirin in each packet.

Direction - You need to take one powder after every eight hours.

Compound powders

Powders mixed from two or more substances constitute compound powders. Afterward, divide it into the desired number of doses. Each powder paper is then dispensed with the solution.

Example - Dispense 8 powders of A.P.C, each powder containing 500mg of A.P.C

Rx, Aspirin 300mg

Paracetamol 150mg

Caffeine 50mg

Procedure - Make sure that each powder is accurately weighed and mixed in ascending order by weight. Each dose should be wrapped in powder paper after weighing 500 mg of the mixed powder.

Preparation of powders

Step 1. particle size reduction

• The powder is created by grinding each ingredient into fine particles; thus, to prepare powder, different procedures and equipment need to be used to reduce the particle size of powder ingredients. This is called comminution.
• As a powder formulation method, the most common way to reduce particle size is to triturate. This is done by placing the chemical in a mortar and grinding it between the mortar and pestle throughout the process using a strong, downward press.

- Making sure that all powder particles are evenly reduced and mixed requires frequent scraping of the sides of the mortar.
- In addition to the levigating agent, the solid is manipulated with a triturating machine to further reduce the particle size, or with a spatula to wet the mixture for further reduction in particle size after it has been triturated.

In the laboratory, certain methods can be used:

• Levigation
• Pulverization
• Trituration

In industrial methods, certain methods can be adopted:

• Hammermill
• Roller mill
• Microfluidics particle reduction
• Bowl chopper
• Colloid mill
• Attrition mill
• Ball mill
• Advance size reduction technologies

Step 2 – preparing the homogenous mixture

One of the following methods may be used to mix the powders:

• Geometric dilution
• Trituration
• Sifting and tumbling
• Speculation

Geometric dilution

If a large amount of diluent has been mixed with potent substances, the method is used to separate the substances. A mortar is used to place the potent drug on the dilute and mix the substances, which is done by triturating the mixture.

An equal volume of diluent is added to the powder mixture in the mortar, and it is triturated again. As diluents are added in equal volume to the mortar mixture at each step, the process is repeated until all the diluents have been incorporated.

Trituration

In addition to reducing particle size, it is also used to mix powders. The glass mortar with a smooth working surface is preferred for particle reduction along with powder mixing. Using a porcelain mortar with a rough inner surface is the best method for blending powder and reducing particle size.

Sifting

In the mixing process, powders are passed through sifters. Processes like this produce an extremely light, fluffy product and are not suitable for the inclusion of potent drugs into diluent solutions.

Tumbling

An electric motor rotates a large container while powders are mixed inside. Industrial blenders are used widely for mixing powders in large volumes.

Speculation

Mixing powders using this method involves moving the spatula over the piece of paper or porcelain tile on which they are to be mixed. When mixing powder or liquid substances that liquefy (eutectic mixtures) the method is very useful.

Step 3 – packaging of powders

A lot of powdered bulk products are packaged in shaker top containers so that topical application is easier and more convenient. In addition to dispensers with wide mouth jars or flip-top lids, wide mouth jars with a flip-top are also available. It is recommended that the jar or plastic container be tightly sealed, especially when compounds with volatile ingredients are present. This will enhance the stability of the compound and offer protection from moisture and light. "For external only use" should be clearly labeled on the packaging.

Double wrapping
Menthol, thymol, citric acid, Pepsin, and other volatile or hygroscopic drugs need double-wrapping to maintain their effectiveness. Drugs with volatile properties should also be double wrapped to prevent the drug from being ruined by the atmosphere. Drugs with volatile properties should also be double wrapped to prevent the drug from being ruined by the atmosphere. Individual powders should be dissolved in a little water or placed on the tongue before being swallowed by the patient.

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