Overview, Advantage And Disadvantage Of Pharmaceutical Standard Compressed Tablet

Pharmaceutical tablets are solid, flat or biconvex dishes, unit dosage form, prepared by compressing a drugs or a mixture of drugs, with or without diluents. Tablet is defined as a compressed solid dosage form containing medicaments with or without excipients. They vary in shape and differ greatly in size and weight, depending on amount of medicinal substances and the intended mode of administration.

Compressed tablets

Tablets are being formed by compressing the granules using the compression machines. A tablet formation takes place by the combined pressing action of two punches and a die.

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Standard Compressed Tablets

These are standard uncoated tablets made by compression using wet granulation, direct compression or double compression. It provides rapid disintegration and drug release. They are mostly intended to exert local action in gastrointestinal tract (GIT). It typically includes water insoluble drugs such as antacid and adsorbents. In addition to medicinal agents, compressed tables usually contain a number of pharmaceutical adjuvants such as diluents, binders, disintegrants, etc.

Principle Of Compression

The punch and die move towards each other with the granules in between. The movement is guided by hydraulic pressure. The resulting pressure is calculated from knowing the area and diameter of both die and punch.

Compression Of Tablet Stages

divided into four distinct stages. These are named as filling, metering, compression and ejection.

Filling

Granules are transferred to the punch die cavity. The position of the lower punch in the die is responsible for the volume of the cavity and subsequently the tablet size. The upper and lower shape of the tablet is determined by the surface of both the punch and die.

Metering

There is a cam below the lower die that help control the amount of granule that remain under the punch. It pushes the die up removing excess granules. The excess granules at the top is the turret table is scratch or push away by another mechanism.

Compression

Both the punch and die move towards each other compressing the granules and the pressure forcing the granules to form tablet. So the distance between the final die and punch will determine the thickness and hardness of the tablet.

Ejection

The punch rises above the turret table. The die rises at the level of the turret table with the already form tablet. A scrapper move along collecting the tablet in a container.

Read Also: Types And Classification Of Pharmaceutical Tablet

Advantages Of Standard Compressed Tablet

1. They are cheap and easy to manufacture in large scale

2. Can be self administered

3. Pain free

Disadvantages Of Standard Compressed Tablet

1. Not all drugs can be formulated as compress tablet

2. Delay onset of action

3. Drug can be degraded by GIT

4. Fix dose that cannot be easily adjusted

5. The odour, colour and taste have not been masked