suppositories
administration: generally for rectal administration
shape: cylindrical with one/both ends tapered
weight: 1-2g
pessary
administration: generally for vaginal administration
shape: oviform, cone-shaped
weight: 1g
nasal bougie
administration: generally for nasal administration
base: gelato-glycerin base
length: 9-10cm long
weight: 1g
urethral bougie
administration: generally for urethral administration
shape: pencil-shaed (3-6mm diameter, 80mm long)
weight: 1g
ear cone
administration: into the ear
base: oleaginous base
application of suppositories
when are suppositories recommended
disadvantages of suppositories for drug delivery
desirable properties of suppository base
types of bases
oleaginous, water soluble/miscible, emulsifying
oleaginous bases
oily/fatty bases
eg: theobroma oil, hydrogenated fatty acids of vegetable oils, monoglycerides of high MW fatty acids
theobroma oil
aka cocoa butter, composed of triglycerides of mainly oleic stearic and palmitic acid, occurs in three crystalline forms-
disadvantage of theobroma oil base
water soluble/miscible bases
does not melt but dissolve slowly in biological fluid, and are commonly prepared from glycerinated gelatin or polyethylene glycols
what does glycerinated gelatin contains
gelatin- for hardness
glycerin- for hydrophilicity (allow base to attract water)
what are the two types of gelatin
advantage of glycerinated gelatin base
2. more easily inserted; suitable for urethral administration
disadvantage of glycerinated gelatin base
2. support growth of mould (need to be hygienically stored)
what are carbowaxes
Polyethylene glycols
what are PEG general formula
HOCH2 (CH2OCH2)n CH2OH,
common MWL 200, 400, 600, 1000, 1500, 1540, 3350, 4000, 6000
advantages of PEG bases
due to higher MP: 1. convenient storage 2. easy insertion 3. no leakage from orifice due to varying solubilities: 4. control of drug release
disadvantage of PEG bases
2. hygroscopic
emulsifying bases
composed of triglycerides with one or more emulsifying agents
witepsol
hydrogenated triglycerides of lauric acid with added monoglycerides