It is the major part of Pharmaceuticals Industries.

1. Presentation on
Tablets Defect and
remedy
Presented By
Likhon Ahmed
Southeast University
Dept. of Pharmacy

2. 1. Twinning
 Two tablets stick together.
 Most common in capsule shaped tablets
Cause –
Coating suspension can not be evaporated.
Remedy –
Reducing spray rate
Increasing pan speed

3. 2.Cracking
Small, fine cracks observed on the upper and lower central
surface of tablets, or very rarely on the sidewall are referred to as
‘Cracks’.
Cause –
• Use of higher molecular weight polymers or polymeric blends
• Higher internal stresses in the film ( more than tensile strength
of the film )
Remedy –
• Use low molecular weight polymer
• Adjust the plasticizer & pigment types and concentration to
minimize internal stresses.

4. 3. Blistering
It is local detachment of film from the substrate forming a
blister .
Cause :
Over heating during spraying coating solution
Remedy :
use mild drying condition .

5. 4.Chipping
 It is the defect where film become chipped and
dented , usually at the edges of tablet .
Cause :
• Excessive attrition during coating process
Remedy :
Increase hardness of the film .

6. 5. Orange peel effects
 It refers to a coating texture that resembles the surface of an
orange .
Cause :
• Rapid Drying
• High solution viscosity
Remedy :
• Use mild drying conditions
• Use additional solvents to decrease viscosity of solution.

7. 6. Bridging
Coating fills in the letter or logo on the tablet .
Cause :
• Improper formulation
• Poor logo design
• Improper application of coating solution
• Improper atomization pressure
• High percentage of solid in coating solution
• High coating viscosity
Remedy :
• Increase plasticizer contents or change plasticizer concentration
• Reduce viscosity of coating solution

8. 7. Filling
The monogram or bisect is filled and become narrow
Cause :
• Applying too much solution
• Higher solution applying rate
Remedy :
Control fluid application rate

9. 8. Blooming (Hazing/dull film)
 Coating becomes dull immediately or after a prolonged
storage . Normally it occurs together with surface roughness.
Cause - using low molecular weight plasticizer.
Remedy - increase MW & concentration of
plasticizer .

10. 9. Cratering
 It is the defect of film coating whereby volcanic-like craters
appears exposing the tablet surface .
Cause –
• Penetration of the coating solution into the
surface of the tablet
Remedy –
• Decrease in spray application rate
• Use of optimum and efficient drying

11. 10. Pitting
 It is defect whereby pits occur in the surface of tablet core
Cause-
• In continuous spreading of film
• temperature of the tablet core is greater than the melting
point of the materials used in tablet formulation.
Remedy –
• control drying temperature

12. THANK YOU