Dosage Forms Exam 2 Flashcards
What are some parenteral medication errors?
Incorrect ingredients
Incorrect strengths
Contamination with pathogens
Contamination with pyrogens
What happened in 2012 with the New England Compounding Center?
They had an outbreak of meningitis from their product
What did the NECC meningitis outbreak lead to?
The Drug Quality and Security Act
What is USP <797> about?
Pharmaceutical compounding–sterile preparations
Which numbers of the USP are mandatory?
<1000
What is a parenteral product?
Medication that is taken into the body or administered in a manner other than the digestive tract
How are parenteral products administered (in practice)?
By injection
What are the benefits of using a parenteral route?
Avoid GI tract, administer directly to specific organ/tissue to minimize systemic side effects
Why do parenteral products have such stringent requirements?
Their administration requires injury to the body/bypassing the body’s natural defense barriers
What are the 3 requirements for parenteral products?
- Sterile
- Particle Free
- Pyrogen Free
What does USP <797> reduce the risk of?
Harm to the patient!
- Microbial contamination
- Excessive bacterial endotoxins
- Variability in strength of ingredients
- Unintended contaminants
- Ingredients of inappropriate quality
What does sterile mean?
Free of microbial organisms
How do you sterilize something?
Steam (autoclave) Filtration Dry Heat Gas (ethylene oxide) Irradiation (gamma rays)
What are pyrogens?
Bacterial endotoxins–produce fever, cause septic shock
Where do pyrogens come from?
Remanants of microorganisms
Does sterilization eliminate pyrogens?
No
What is the risk of pyrogens?
Septic shock/anaphylactic shock
What is septicemia?
Infection of the blood
What is septic shock?
Acute reaction to bacterial endotoxins (pyrogens)
Why do sterile preparations have to be particle free?
Foreign particles can trigger an immune response
Produce damage to lungs
Produce damage to kidneys
Kill people
What are the 6 types of parenteral products?
Solutions ready for injection
Dry, soluble preparations ready to be combined with a solvent before use
Suspensions ready for injection
Dry, insoluble preparations ready to be combined with a vehicle before use
Emulsions (like parenteral nutrition)
Liquid concentrates ready for dilution prior to administration
What is a [DRUG] injection?
Liquid preparations that are drug substances
What is a [DRUG] for injection?
Dry solids that need to have vehicles added to yield solutions that meet requirements for injection
What is a [DRUG] injectable emulsion?
Liquid preparation of drug substances dissolved or dispersed in a suitable emulsion medium
What is a [DRUG] injectable suspension
Liquid preparations of solids suspended in a suitable liquid medium
What is a [DRUG] for injectable suspension?
Dry solids that yield preparations that meet requirements for injectable suspensions when vehicle is added
Difference between purduemycin injection and purduemycin FOR injection
“For” means that it is not ready to use! Has to have vehicles added before being injected
What is LVP?
Large Volume Parenteral–single dose injections in a container more than 100 mL
What is small volume parenteral?
Injection of 100 mL or less
Is a mistake worse in an LVP or a small volume parenteral?
LVP
What is a vehicle?
Solvent/medium for the administration of therapeutic agents
What is the most common vehicle?
Water
What is the preferred vehicle?
Water
What are the 3 types of water used in parenteral products?
Water for injection
Sterile water for injection (SWFI)
Bacteriostatic water for injection (BWFI)
What is WFI?
Water for injection–pyrogen free, non sterile, single use sealed container
What is SWFI?
Pyrogen free, sterile, packed in sealed containers <1000mL
What is BWFI?
Pyrogen free, sterile with antimicrobial agent added
Which water shouud you use for parenterals?
SWFI
Can you inject plain water? Why not?
NO - it causes hemolysis because it is so hypotonic
What preferred tonicity of parenteral products?
Isotonic
What is the preferred pH of parenteral products?
Physiological
Can intra-spinal injections have preservatives?
No
What are 4 common isotonic vehicles?
0.9% NaCl Solution (NS)
D5W
Ringer’s Solution (NS w/K and Ca)
D2.5W1.2NS
What is the ideal solvent for parenteral products?
Water
What are water miscible cosolvents used for?
To solubilize drugs in water vehicle
What are some cosolvents?
Alcohol Polyethylene glycol (40%) Propylene glycol (10%)
When are cosolvents often used?
IM injections
Why can PEG be used at a higher IV concentration than ethyl alcohol?
To prevent hemolysis–ethyl alcohol has a higher hemolytic potential than PEG
Can oil be injected into veins?
No, causes embolus
Can oil emulsions be injected into veins?
Sure–in small enough droplets that they won’t cause embolus
Can oil injections be used for IM?
Yes
When are antimicrobial preservatives used?
With multidose preparations ONLY
What is the most common preservative?
Benzyl alcohol 0.9%
What is the second most common preservative?
Parabens–methyl and propl
Are antimicrobials more effective in O/W or W/O?
O/W
What causes some compatibility issues with antimicrobial preservatives?
Polysorbate and PVP inactive them
Do single use preparations have antimicrobial preservatives?
No–and they can NOT
What populations should benzyl alcohol NOT be used in?
Neonates–gasping syndrome
What populations should not contain antimicrobial preservatives?
Neonates
What injection route cannot contain antimicrobial preservatives?
Intra-spinal (must be single use)
What are some common pH buffers?
Citrates
Acetates
Phosphate
Which pH buffer has the potential to be fatal?
Phosphate!!
What is the caution with citrate buffers?
They are irritating via IM or SC rate, but safe by IV
Which buffer has a dangerous reaction with calcium?
Phosphate
When do phosphate and calcium have to be given together?
TPN preparations
When is it important for a parenteral product to have a physiological pH?
In a solution with a BUFFE (not in a non-buffered solution)
Why do unbuffered solutions NOT have to be at physiological pH?
They are quickly diliuted into physiological pH after injection–buffers are forced to remain at a different pH
What are some antioxidants?
Metabisulfate salts (low pH)
Bisulfite (medium pH)
Sulfite (high pH)
Ascorbic acid
What is the most common chelating agent?
EDTA
How do you inject a solution that is not isotonic?
- Small volumes
- Slowly
- Into central vein
All to dilute the hypertonic solution
What is the best type of glass to use to contain parenteral products?
Type I
The containers and closures are considered ingredients of a parenteral product.
True
What is the draw back of a flip off cap/metal cover?
Does not guarantee sterility–just protects the rubber stopper
What is an ampule?
Glass, single use container; tight and uniform