Tablet Technology

Question 1

Define a Tablet

Answer 1

Tablet can be defined as unit form of solid medicament prepared by compression. Most consist of mixture of powders which are compacted in a die to produce a single rigid body.

Question 2

What are the advantages of Tablets?

Answer 2

- Greatest dose precision and least content variability.
- Their cost is lowest of all oral dosage forms.
- They are the easiest and cheapest to package and ship.
 Product identification is the simplest.
- Easy to swallowed.
-They tend themselves to a special release profile product such as enteric or delayed release product.
- They have the best combined properties of chemical, mechanical and microbiological stability of all oral forms.
- They are better suited for large scale production.

Question 3

What are the disadvantages of Tablets?

Answer 3

-Some drugs resist compression into dense compacts owing to their amorphous nature or low density character.
- Drugs with poor wetting, slow dissolution properties maybe difficult or impossible to formulate and manufacture as tablet that will still provide adequate or full drug bioavailability.
- Bitter tasting drug, drugs with objectionable odour or drugs that are sensitive to oxygen or atmospheric moisture may require encapsulation or entrapment prior to compression or tablet may require coating.

Question 4

What are the basic components of a tablet machine?

Answer 4

• Hopper (s) for holding and feeding granulation to be compressed.
• Dies that define the size and shape of the tablet.
• Punches for compressing the granulation within the dies.
• Cam tracks for guiding the movement of the punches.
• A feeding mechanism for moving granulation from hopper into the dies.
  Tablet presses are classified as either hand tablet machines or
  multi-station rotary presses.

Question 5

What is the uniformity of weight or weight variation tolerance test?

Answer 5

This test is carried out by collecting a sample of
tablets, normally 20, from a batch and determining their individual weights. The average weight of
the tablets is then calculated. The sample complies with the standard if the individual weight do not
deviate from the mean more than is permitted in terms of percentage.

Question 6

What is the uniformity of drug content test?

Answer 6

This is carried out by collecting a sample of tablets, normally 10, followed by a determination of the amount of drug in each. The average drug content is calculated and the content of the individual tablets should fall within specified limits in terms of percentage deviation from the mean.

Question 7

How is the disintegration test carried out?

Answer 7

The test is carried out by agitating a given number of tablets in an aqueous medium at a defined temperature & the time to reach the end point of the test is recorded.
* The preparation complies with the test if the time to
reach this endpoint is below a given limit.

Question 8

Why are dissolution tests carried out?

Answer 8

1. To evaluate the potential effect of formulation and process variables on the bioavailability of a drug.
2. To ensure that preparations comply with product specifications.
3. To indicate the performance of the preparation under in vivo conditions.

Question 9

What are the two apparatus used for dissolution testing?

Answer 9

• Apparatus I: Rotating basket method

* Apparatus II: Paddle method

Question 10

Why are mechanical strength rest carried out?

Answer 10

1. To assess the importance of formulation and production variables for the resistance of a tablet towards fracturing and attrition during formulation work, process design and scaling up.
2. To control the quality of tablets during production (in-process and batch control).
3. To characterize the fundamental mechanical properties of materials used in tablet formulation.