Defects in tablets and their remedies

 

Defects in Tablets Dosage Form.

Defects in tablets and their remedies;

•Following types of defects found in tablets during compression;

1. Picking

2. Sticking

3. Capping

4. Lamination

5. Double compression

6. Mottling

7. Weight variation

8. Harness variation

 •Reasons and remedies:

1. Picking:

It occurs due to the sticking of powder to the punches. 

 

It usually happens due to the addition of a substance with a low melting point. Resolve the problem by adding lubricant of high melting point.

 

2. Sticking:

It is the result of adhering the tablet material to the die walls. 

There are three main reasons.

 

*pressure during compression is not sufficient therefore increase the pressure.

*excess amount of moisture is also one of the reasons therefore dry the granules properly.

*Problem May develop due to the rough surface of punches and dies therefore dismantle them, change the dies and polish the punches properly with polishing material before resetting.

 

3. Capping:

in this situation topmost or lowermost layer of the tablet separates during compression. This defect occurs mainly due to the following two reasons.

 

*entrapment of air during compression. It may be avoided by pre-compression.

*Deep concave punches may be another reason. the defect can be rectified by replacing them with Flat punches.

 

4. Lamination:

 In this case, granules are too much dry. Mix hygroscopic substances like sorbitol or cellulose to rectify the defect.

 

5. Double compression:

monogram print on the surface of the tablet have double marks. 

It is due to the movement of the lower punch during tablet ejection.

Use keys to fix the lower punches to prevent their movement.

We can also use the anti-turning device to prevent punch rotation.

 

6. Mottling: 

Mottling is the unequal distribution of colour in the compressed tablet.

 

Colour migrates to the outer surface during drying. The problem can be resolved either by a change of lubricant, a change of binder, drying at a low temperature or reducing the particle size.

 

7. Weight variation:

if the weight of the tablet does not comply with the standard range defined in the BMR and changes frequently during machine operation Is called a weight variation problem.

This may be due to the poor flow of granules or the high speed of the turret. Poor flow of granules will improve by using a substance like talcum powder.

Poor mixing of granules and improper size of granules result in weight variation this need to be sieved and remixed.

 

8. Hardness variation:

It occurs due to the improper space adjustment between the two punches according to the amount of powder. Problems can be resolved by the correct use of tooling and proper use of a wheel adjustment knob.

 

• Sources of defects in tablet compression may be due to the following reasons;

 

1. Problems in the formulation

 

2. operation equipment may be another reason.

 

3. problem may be created by the combination of the above two reasons.

 

•Tablet dosage form is one of the important routes of administration of medicine to the patient. It is easy to handle and is taken without any help from health professionals as compared to injection as patients will have to seek help from a doctor or nurse while in the case of liquid dosage form it is difficult to handle as compared to a tablet.

 

•Tablet is manufactured through different stages starting from dispensing to coating, blistering and final packing. It is therefore important to keep the care of its strength as well as its proper disintegration and dissolution in the stomach. It is however difficult to swallow for children and aged persons.

 

•Tablet is manufactured in a dusty environment. the main issue is to maintain cleanliness, particularly in granulation and compression areas. There must be a proper exhaust system before the start of any operation. Collection of powder from the machine during operation is very important otherwise powder will accumulate on the machine and tablets resulting in dusty conditions unsuitable for production, therefore, the machine exhaust system must be activated before operation.