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26 Cards in this Set
- Front
- Back
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Suppositories 1
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1 Solid dosage forms of various weights, sizes and shapes, adapted for administration into the rectal, vaginal, or urethral orifice of the human body
2 They usually melt, soften, or dissolve at body temperature |
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Suppositories 2
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A suppository may act as a protectant or palliative to the local tissues at the point of introduction (site) or as a carrier of drug substances for systemic or local effect
1 Local use will include the treatment of hemorrhoids, itching (irritation), inflammation, and infections 2 Systemic use will include the treatment of nausea, vomiting, asthma, and pain |
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Rectal Suppositories
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1 Rectal suppositories are ideally used for children and patients who cannot take per oral (po) dosage forms
2 ACETAMINOPHEN (Rectal Suppository) Dulcolax Suppository-For the treatment of occasional Constipation Bisacolax, Bisacodyl Suppositories USP laxative |
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Vaginal Suppositories
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Vaginal suppositories are usually oviform or coned shaped for the vagina
Weigh around 5 g Examples: Miconazole3, Dinoprostone, Tydone (povidone iodine) |
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Urethral Suppositories
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Urethral suppositories (bougies) are slender and pencil shaped - M.U.S.E. (Medicated Urethral Suppository) - also known as MUSE and as alprostadil, is a tiny medicated pellet that is inserted in the male urethra
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Uses of Suppositories in situation/conditions like:
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1 Comatose or unconscious
2 Nausea and vomiting 3 Epileptic or other seizures 4 Blocked or removed GI Tract 5 Drugs with poor bioavailability |
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Fatty or oleaginous bases (Suppository Bases)
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Cocoa butter (Theobroma oil)
Fattibase® Witespol bases MBK® |
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Water-soluble bases (Hydrophilic Bases)
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PEG
Glycerinated gelatin |
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Cocoa butter or Theobroma oil (Fatty Bases)
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1 Widely acceptable base for compounding suppositories
2 Non-irritating and non-reactive 3 Melts quickly at body temperature (at 370C) 4 Must store in refrigerator 5 Exhibits polymorphism (four different forms) 6 Do not heat cocoa butter base above 340C |
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Fatty Base Disadvantages
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1 Fat-soluble drugs within a suppository tend to be trapped within the oil and may not enter the aqueous body fluids while water- soluble drugs within the cocoa butter tend to be released fast
2 May leak from the body orifice 3 Melts in warm weather 4 Liquify when substances like phenol and chloral hydrate are incorporated |
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Fattibase® (Fatty Bases)
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1 Suppository base pre-blended
2 Properties similar to cocoa butter except for low irritation |
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Witespol bases (Fatty Bases)
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1 About 12 suppository bases
2 May be mixed to provide a wide range of melting points 3 Contain emulsifiers, so may absorb limited amounts of water |
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MBK® (Fatty Bases)
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1 Suppository base-preblended
2 Properties similar to cocoa butter base except for low irritation 3 Not so susceptible to polymorphic changes as cocoa butter (theobroma oil) |
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Polyethylene Glycol (PEG) (Water Soluble Bases)
Most popular in this class of bases |
1 Physical properties change with molecular weight: PEG’s with lower molecular weights(200-600) are liquids where as the higher mol wt. (> 1000) PEG’s are solids
2 Generally a combination of PEG’s (solid and liquid) are used so as to achieve the desired hardness and melting point |
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Polyethylene Glycol (PEG) (Water Soluble Bases)
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1 Dissolve slowly in the body aqueous fluids
2 Incompatible with many drugs 3 Do not support mold growth 4 Can be stored without refrigeration in tightly closed container |
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Glycerinated gelatin (Water Soluble Bases)
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1 Mixture of gelatin (20%), glycerin (70%) and water (10%)
2 Used to make vaginal suppositories only 3 Hygroscopic (protect from moisture) 4 Don’t melt but dissolve 5 For local application of antimicrobial agents and progesterone 6 Glycerin suppositories (short term treatment of constipation) |
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Rate Limiting Step in Drug Release
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Oleaginous: MELTS => spreads
Hydrophilic: dissolves => DIFFUSES |
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Mechanism of Drug Release
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1 Drug Release depends on partitioning coefficient of the drug between aqueous & organic solvents
2 K= oil/water =0.1/.0001= 1000 3 If we use an oil soluble drug, the oleaginous base will retain it, very slow/no partitioning to the water phase, say, rectal fluids |
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Suppository Molds
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1 Various types of molds stainless steel, plastic, aluminum, brass
2 Various shapes and sizes of plastic and rubber molds are generally disposable 3 Steel and aluminum molds are reusable after scrupulously cleaning and lubricating with PAM (vegetable oil) 4 Temporary molds are 1cc syringe used for urethral and infant suppositories |
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Suppositories can be extemporaneously prepared by three methods
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1 Hand rolling and shaping method
2 Fusion method (molding from a melt) 3 Compression method |
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Hand Rolling and Shaping
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1 This method involves molding the suppository with fingers after formation of a paste
2 A finely powdered drug is mixed with the base in a mortar and pestle, using levigation and geometric dilution techniques 3 The uniformly mixed paste is then kneaded further, rolled into cylinder, and divided into the correct number of suppository 4 Each small cylinder is then rolled by hand until a suppository shape is achieved |
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Fusion (Molding) Method
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Molding is the most frequently used method for both small and commercial scale preparation of suppositories
The following are the steps to prepare suppositories by molding: 1 Melt the base 2 Add the drug to the base 3 Pour the melts into molds 4 Allow the melt to cool and congeal into suppositories 5 Remove the hardened suppositories from the mold. Most suppository bases are suitable for molding |
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Compression
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1 Suppository base and drugs are forced into special molds using suppository making machine
2 A uniform mixture of drug and base is prepared like that of hand-rolling method 3 The mixture is then placed into a suppository compression device, pressure applied, and the mixture forced into lubricated (with mineral oil) compression mold cavities 4 The mold is then cooled and the suppositories are ejected 5 This method is specially useful for drugs that are heat sensitive and substances that are insoluble in bases |
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Pessaries
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1 Pessaries are solid, bullet-shaped preparations designed for easy insertion into the vagina
2 They can be inserted using the fingers, or may come with an applicator 3 Pessaries are normally made of a solid vegetable oil (base) that contains the drug 4 The drug is gradually released into the vagina as the pessary dissolves at body temperature 5 Examples: Betadine (povidone iodine) vaginal pessaries, Canesten (clotrimazole) vaginal pessaries- antifungal |
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Vaginal Inserts 1
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1 Progestasert system (Alza Corpoartion)
2 Slowly releases 60µg/day for 1 year or more after insertion continuous release provides local rather than systemic action 3 T-shaped device to ensure comfort, safety and retention 4 Contains progesterone suspended in silicone oil; barium sulfate added to make it radiopaque 5 EVA membrane surrounds the drug core controls the rate of drug release |
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Vaginal Inserts 2
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1 Dinoprostone(Cervidil, Forest Pharmaceuticals) is a thick, flat rectangular polymer slab enclosed in a pouch of a knitted polyester retrieval system
2 Designed to release dinoprostone in vivo at a rate of about 0.3 mg/hour 3 Contains 10mg of dinoprostone in 236 mg of cross-linked polyethylene oxide-urethane polymer slab 4 It is inserted veginally and removed upon onset of active labor or 12 hours after insertion 5 It is a matrix system |
