Compounding II: Equipment, Stability, & Excipients Flashcards
The wider the mouth of the cylinder, the _________ the accuracy.
lower
- graduate cylinders are more accurate than conical graduates or beakers
A graduate should not be used to measure volumes less than ____% of the graduate’s capacity.
20%
For drawing up a medication, should you use the exact size syringe needed?
No, you should not use the exact size syringe needed because the plunger can easily become dislodged. Select the closest syringe size above the size needed. Do not add two different syringe sizes for a dose.
difference between a volumetric pipette & a Mohr pipette
volumetric pipette - draws up a set volume only, which is the volume it can hold
Mohr pipette - is graduated & used to measure different volumes; commonly used in compounding
What type of balance is the “older” balance that is still used but less commonly than the electronic balance?
Class III torsion balance (sometimes called a Class A balance)
Explain sensitivity requirement (SR) and minimum weighable quantity (MWQ) of a torsion balance.
Torsion balances have a sensitivity requirement (SR) that is most often 6 mg, meaning 6 mg can be added or removed before the dial moves 1 division
MWQ = SR / acceptable error rate (0.05 or 5%)
ex. MWQ = 6 mg / 0.05 = 120 mg
Which balance is used most commonly?
top-loading electronic balance (called an analytical balance or scale)
- simple (not necessary to calculate a MWQ)
- has higher sensitivity
- must “tare” or “zero out” the balance after placing weigh boat or glassine paper on scale
- always place material to be weighed on a weigh boat or glassine paper (never directly on the balance)
A compounding pharmacy needs how many and what kinds of mortars & pestles?
at least one glass & at least one Wedgewood or porcelain
Glass mortars are used for…
liquids, such as suspension & solutions, and for mixing compounds that are oily or can stain
Wedgewood mortars have a rough surface & are preferred for…
grinding dry crystals & hard powders
Porcelain mortars have a smooth surface, & are preferred for…
blending powders & pulverizing gummy consistencies
When would a steel (metal) spatula NOT be used?
if making a mixture that contains metallic ions
Sieves are sifters similar to those used in baking. After a powder has been ground fine, it is sifted in order to ensure…
a uniform particle size
Ointment mills & grinders _________ the particle size, which ___________ the surface area & the rate of drug absorption.
Ointment mills & grinders decrease the particle size, which increases the surface area & the rate of drug absorption.
Capsule sizes for human use range from _____ (the largest size) to _____ (the smallest size). Veterinary pharmacists can order larger capsule sizes for use in larger animals.
000 (largest) to 5 (smallest)
Capsules can be ________ or __________.
soft gels or hard shells, which are most commonly used for compounding
- shells are made of gelatin, which is pork-derived & will not be suitable for some patients, or from hypromellose or a similar plant-derived product
Ingredients that are recommended for use will be listed in…
either:
- USP National Formulary (USP-NF)
- Food Chemical Codex (FCC) substances list
Preferably, ingredients should be manufactured at an FDA-registered facility. If any substance comes from a non-FDA registered facility, a __________________ should be obtained.
Certificate of Analysis (CoA), confirms the specifications & quality
Surfactants ___________ the surface tension (i.e., the interfacial tension) between two ingredients (or phases) in a preparation to make them more _________.
Surfactants lower the surface tension (i.e., the interfacial tension) between two ingredients (or phases) in a preparation to make them more miscible (i.e., easier to mix together).
Surfactants are ____________.
a. lipophilic
b. hydrophilic
c. amphiphilic
c. amphiphilic
- both hydrophilic (on one side) & hydrophobic (on the other)
Surfactants are called by a variety of names, depending on the use or the type of preparation. What are the types of surfactants?
WETTING AGENTS
EMULSIFIERS
SUSPENDING AGENT
LEVIGATING AGENTS
FOAMING AGENTS
Describe wetting agents
reduce surface tension b/t a liquid & solid (ex. a fine powder that will be incorporated into a suspension is wetted with a wetting agent)
Describe emulsifiers
emulsion is a mixture of two or more liquids that are immiscible; emulsifier added to help keep the liquid droplets dispersed throughout the liquid vehicle
Describe suspending agents
- suspension is a solid dispersed in a liquid; suspending agent added to help keep solid particles from settling
- can be called dispersants (or dispersing agents)
- can be a plasticizer, meaning to make a preparation easier to shape or mold (ex. sorbitol can be used as a plasticizer for gelatin capsules)
