suppository -formulations

how many doses are in a suppository

single dose

what are the sahpe and volume of a suppository suitable for

rectal administriation

what do suppositories contain

one or more activ substance dispersed or dissolved in a suitable bases which may be soluble or dispersible in water and may melt at bodily temperaute

what expients are in a suppository

diluents adsorbents surfactamts lubricants anti-microbial preservatives and colouring matter

what is an advantage of using a suppository

no first pass metabolisn

why might you use a suppositriy

You may have a petient who is not able to take a tablet or want to be (such as when they are nautious,migrane treatment,vomiting

In these cases the tablets will come back out

A patient who is unconscious

Easier if it is availibe in a suppository form

Good for children,

what is the only blood vessels in the gi tract which dont go near the liver

-the rectal weins are the only blood vessels in the GI tract are not connected to the liver and you can then circumvent the liver

what is the ph in the rectum

constant pH of 7.5 in the rectum/the colon

what are the requirements for the bases used in a suppository

1-non-irritant locally,chemically inert and stable

2-compatable with a wide variety of drugs

3-able to shrink slightly on cooling

4-able to incorperatue aqueous and oily liquids

5-capable of melting and solidifying over a narrow temperautre range

what are the 4 availiable suppository bases

1-theobroma oil

2-semi-synthetic glycerides

3-glycerol-gelatin mixtures

4-macrogol

what are the typical content of theobroma oil

steric acid

oleic acid

palmitic acid

linoleic acid

what happens to theobroma oil on storage

becomes rancid

what emulsifying properties does theobroma oil have

poor

what happens to the melting point of theobroma oil with some drugs

-what should you do to combat this

lowers

add beeswax

what form of theobroma oil do we want

the beta form

what are the semi-synthetic glycerides from

vegtable oils

-mixture of mono-di and tri glycerides

is the semi-synthetic glycerides saturated

yes

melting range of the semi -syntheitic glycerides

34-36

what are the disadvantages of semi-synthetic glycerides

-lower viscocity

-become brittles when cooled to rapidly

what is the composotion of the glycerol-gelatin suppository base

gelatin 70g

peurified h20 -14 g

glycerol -dufficnet

does glycerol geltatin melt

no,it dissolves

is glcyerol gelatn hydrocopic

yes very

what is the formulation of macrogol

macrogol 1000-75%

macrogol 4000-25%

is macrogol a non-fatty base

yes

what are the advantages of macrogol

physiologically inert

-not prone to contamination by microbes

disadvantages of macrogol

-incompatable with phenolic drugs

-brittleness and crystal growth upon storage

-more irritating than fatty bases

what is the most common method for extemporaneous compounding

molding

what amount of heat is needed for extemporaneous compounding

minimum heat

define the displacement value of the drug

the amount of the drug that would displace 1g of suppository base