Shared Flashcard Set

Details

Ceutics Exam 3, Part 1
Semisolids
39
Pharmacology
Professional
03/07/2012

Additional Pharmacology Flashcards

 


 

Cards

Term
What are the semisolid dosage forms?
Definition
Semisolid dosage forms pertain to the use of ointments, creams, gels, lotions, and similar preparations as drug delivery systems.

Topical agents
Term
Are semisolids used for local or systemic effects?
Definition
Both
Term
If a semisolid doesn't have a therapeutic drug, what can it be used for?
Definition
They could be used for a sun protectant or lubricant
Term
Define ointments
Definition
Ointments are semisolid preparations intended for external application on the skin or mucosal surfaces.

They primarily consist of the drug and a base (vehicle).
Term
List the four categories of ointments
Definition
1. Oleaginous base (aka. Hydrocarbon base)
2. Absorption base
3. Water-removable base
4. Water-soluble base
Term
Describe oleaginous bases
Definition
-Immiscible with water
-Difficult to wash
-Occlusion, prevents water escape
Term
Give three examples of oleaginous bases
Definition
Petrolatum, white ointment and yellow ointment
Term
Define absorption bases
Definition
These bases allow the absorption of water or aqueous drug solutions resulting in the formation of water-in-oil (w/o) emulsions.
Term
List some properties of absorption bases
Definition
-Emollient effects (though not as much as oleaginous)
-Difficult to wash
-W/O
Term
Give two examples of absorption bases
Definition
Hydrophilic petrolatum and lanolin
Term
List properties of water removable bases
Definition
-O/W
-Easily washable
Term
Give an example of a water removable base
Definition
Hydrophillic ointment
Term
Define water-soluble base
Definition
These bases do not contain any oleaginous components, and are mostly used for incorporation of solid substances.

aka Greaseless base
Term
Give an example of a water soluble base
Definition
Polyethylene glycol (PEG)
Term
What are the two general methods to make an ointment?
Definition
Incorporation and fusion
Term
Define incorporation (in preparing an ointment)
Definition
Ointment ingredients in smaller quantities (drug, excipient etc.) are incorporated into the larger quantity (base).
Term
Define Unguator
Definition
An electronic mortar and pestle for ointments.

Allows a pharmacist to place the ingredients in a plastic ointment jar with a special lid that allows for a mixing blade to be used to mix the ingredients in the dispensing container.
Term
Define levigation
Definition
A process of mixing the solid material in an insoluble vehicle to make a smooth dispersion

Reduces solid particle size
Term
If an ointment is w/o, what is usually the levigating agent during preparation?
Definition
Mineral oil
Term
If an ointment is o/w, what is usually the levigating agent during preparation?
Definition
Glycerin
Term
How do you add aqueous drug to oleaginous base?
Definition
The solution is first incorporated into a minimum amount of hydrophilic base and the mixture is then added to the hydrophobic base.
Term
Define the fusion method of preparing an ointment
Definition
All or some of the ointment ingredients are combined in a porcelain dish or glass beaker, by melting together and cooled with constant stirring until congealed
Term
If using the fusion method, do you add volatile oils and heat sensitive ingredients when adding the rest?
Definition
No, wait until it has cooled down
Term
How are ophthalmic preparations different from other ointments?
Definition
Ointments and other semisolid dosage forms (discussed later in this notes) must meet USP tests for microbial content, minimum fill, packaging, storage, and labeling. For ophthalmic ointments, additional tests for sterility and metal particle contents must be met.
Term
List some antimicrobial preservatives that can be put in ophthalmic ointments?
Definition
methyl- or propyl-paraben
phenols
benzoic acid
sorbic acid
quaternary ammonium salts
Term
Define creams
Definition
Creams are semisolid emulsion preparations containing the drug dissolved or dispersed in a suitable base (usually o/w emulsion; rarely w/o).
Term
How is a cream immediately distinguishable from an ointment?
Definition
Creams have a creamy appearance as a result of reflection of light from the emulsified phases. This distinguishes them from simple ointments which are translucent.
Term
When are creams used, and why is this better than using an ointment?
Definition
Creams find applications in topical skin products and in products used rectally and vaginally.

Creams are preferred to ointments because they are easier to remove, and are better for acne because they dry out the skin.
Term
For what use are ointments better than creams?
Definition
Ointments hydrate the skin, so they are better than creams for dry skin
Term
Define gels (aka jellies)
Definition
Semisolid systems consisting of dispersions of molecules in an aqueous vehicle rendered jellylike by the addition of a gelling agent.
Term
List gelling agents
Definition
Synthetic macromolecules such as carbomer 934

Cellulose derivates such as carboxy- or hydroxypropyl-methylcellulose

Natural gums (e.g. tragacanth, pectin)
Term
What happens if you leave a gel standing too long?
Definition
Gels thicken on standing, forming a thixotrope, and must be shaken before use to liquefy the gel and enable pouring (e.g. milk of magnesia).
Term
List some semi-solid dosage forms other than ointments, creams, or gels
Definition
Pastes (zinc oxide paste for diaper rash), lotions (antimicrobial), plasters (salicylic acid plaster used on the toes for removal of corn), and glycerogelatins (zinc gelatin for varicose ulcers)
Term
How are semisolids packaged?
Definition
Jars, tubes or syringes.

The packaging material is first tested for compatibility and stability with the intended product.

May include a special applicator
Term
How are ointments in jars packaged?
Definition
Jars are filled by carefully transferring the weighed amount of semisolid into the jar with a spatula. The semisolid is packed avoiding entrapment of air. Ointments prepared by the fusion method (heating) may be poured directly into the jar to congeal inside it.
Term
How are ointments in tubes packaged?
Definition
Tubes are filled with the semisolid from the open back, opposite to the cap end. Ointments prepared by the fusion method may be poured directly into the tubes. The bottom of the tube is flattened, folded, and sealed with a crimping clip.
Term
How are ointments in syringes packaged?
Definition
Syringes are filled either by drawing the semisolid into the barrel using the plunger or by removing the plunger and filling through the back end of the syringe. The plunger is then reinserted.
Term
Describe USP test 751
Definition
Metal Particles in ophthalmic ointments
Term
On hairy skin, are ointments or creams more appropriate?
Definition
Creams are better on hairy skin
Supporting users have an ad free experience!