# Displacement value: Suppository The volume of suppository for particular mould in uniform but its weight will vary because of difference of density of base & medicament used. For this displacement valve of medicament is taken in consideration.

Displacement value is defined as : The quantity of drug which displace one part of the base.

The Displacement value of a given medicament can be determined as

B= Indicate Base; M indicate= Medicament/Drug;

a= amount of pure base suppository (without medicament/drug);

d= amount of medicament/drug;

c=amount of base after medicament is incorporated

Example”-

Q. Calculate the displacement of medicament in cocoa butter suppositories containing 40 % medicament, prepared in 1 gm suppository Mould. The wt of 10 medicated suppositories is 15 gm.

A) 6

B) 10

C) 15

D) 4

A

Solution:

Wt. of 10 Pure base suppositories/’a’ = No. of suppositories x Mould size

a= 10 x 1 gm= 10 gm

Wt. of 10 Medicated suppositories(base+ medicament) ”= 15 gm;

Since suppositories contain 40 % Medicament so amount of amount= 40 % of 15 gm= (40/100) x 15 gm= 6 gm medicament/drug

So there is 6 gm is medicament than amount of base is= total wt of suppositories– wt of medicament=15-6= 9 gm base

so Displacement value= d/ (a-c)=6/(10-9)=6/1=6

Q. Each Theobroma oil suppository contains 500 mg of Zno , when prepared in 1gm suppository mould . What will be the quantity of base in 10 medicated suppositories? (D.V. of Zno is 5)

• A) 9 ml
• B) 9 gm
• C) 5 ml
• D) 5 gm

B

SOLUTION:

Displacement value of ZnO=5 is given

One Medicated Suppository containing 500 mg of Zno, So total 10 medicates suppositories containe ZnO=500 mg x 10=5000 mg or 5 g ZnO so value of ‘d‘=5g

Wt of an one pure base Suppositories 1 g so Weight of 10 Pure base suppositories = 1×10= 10 gm or 10000 mg= so value ofa’=10 gm

Now we have to find out the value of ‘c’

Displacement value = d/(a-c)=

5= 5 g/(10-c)={ 5/5=10-c}={1=10-c}

1+c= 10

c=10-1=9 gm

Displacement value of Drug= d/(a-c)

Pharmaceutical Suppository: Introduction

Type of Pharmaceutical Suppository

Preparation of Pharmaceutical Suppository

Evaluation of Pharmaceutical Suppository

MCQ practice Quiz of Pharmaceutical Suppository