Pharmaceutical Technology. How to calculate Displacement value for suppository.

1. Displacement Value of
Suppository.
Presented By
Miss Sudipta Roy
Designation: Assistant Professor
Place : Sanjivani College of Pharmaceutical Sciences
Rajota, Rajasthan

2. Definition of Displacement value.
• The quantity of the drug that displaces one part of
the base.
• Displacement value of the medicament= d/(a-c)
• Where d g = Part of medicine in medicated
suppository from b (total quantity of medicine)
• a g = quantity of base in blank suppository
• c g = Part of base with medicine from b ( total
quantity of medicine ) in medicated suppository.

3. • Total a g = base, medicine is b g = c g (base )+ d g
(medicine)
a g
blank suppository only
base
b g = c g + d g
medicated suppository

4. Let's Start to understand
displacement value with example of
Preparing Suppository.
1. Prepare and weigh 6 suppositories containing theobroma
oil or any other base.
Total weight of theobroma oil in blank suppository = a gram
2. Prepare and weigh 6 suppositories containing 40%
medicament to use theobroma oil as base.
Total weight of theobroma oil present in medicated
suppositories,
As 40% medicament will be present in suppository, then
remaining theobroma oli will be 60%.
Say , 40% medicament is = b gram

5. • So, Total quantity of medicament is b gram in suppository divided into two parts
medicament is 40% and theobroma oil is 60%.
• So total quantity of theobroma oil present in medicament in medicated suppositories (c
gram) =(60/100*b) gram
• Total quantity of medicament present in medicament in medicated suppository (d gram ) =
(40/100*b) gram
• So total value of theobroma oil base a gram in blank suppository= total value of medicine
(d gram) + base (c gram)
• So its equivalent, displaced quantity of medicament d gram = (a-c) gram theobroma oil
• So (a-c) gram theobroma oil displaces medicament in suppository d gram.
• So, displacement value of 1 g of base with medicament = d/(a-c)
• Displacement value has no unit.
• As total theobroma oil requires for 6 suppository without medicament = a g
• As total theobroma oil requires for 6 suppository with medicament = c gram

6. Let's Start to understand
displacement value with example of
Preparing Suppository.
• Cocoa Butter Suppository:
• Formula:
• Iodoform - 0.9 g
• Cocoa Butter Sufficient Quantity.
• Make Suppositories.
• Send 8 Suppositories of 2 g each.

7. • Direction :
One Suppository to be inserted into rectum at bed
time.
Note : Displacement value of Iodoform is 4.0 .

8. • Calculation :
• Weight of Cocoa Butter for one Suppository = 2 g
• Total weight of Cocoa Butter for 10 Suppositories =
10*2 g = 20 g
• Weight of iodoform for one suppository = 0.9 g
• Weight of Iodoform for 10 Suppositories = 0.9 g *
10 = 9 g

9. Displacement Value of Iodoform = 4.0
The quantity of cocoa butter required
= Total amount of base - (Total amount of
drug/Displacement Value)
= 20 - 9.0/4.0
=20 - 2.25
= 17.75 g

10. • Formula for 10 Suppositories -
• Iodoform - 9.0 g
• Cocoa Butter - 17.75 g

11. • Storage and Packaging:
• Suppositories are packed in shallow partitioned
card board boxes.
• To hold suppositories in upright position not to
allow to come in contact with each other.

12. • Suppositories directly moulded into primary
packaging made of plastic material or aluminium
foils.
• Moulds are sealed.
• Excess are trimmed off and finally packed in
cartoons.
• To store in a cool place to retain their shape at
room temperature.