Lab 11 Flashcards
Sterile means
Free from all microorganisms
Preparations must be sterile when….
-there is a possibility of infection
-when they are instilled directly into body tissues and cavities, bypassing the natural defenses of the body
Explain ophthalmic preparations
STERILE, can be liquid, semi-solid, or solid preparations that contain 1 or more APIs
Ophthalmic preparations are intended for application where?
To the conjunctiva, conjunctival sac, or the eyelids
Ophthalmic preparations are applied _____ to the eye to treat ____, ____, ____, and ——-
Ophthalmic preparations are applied TOPICALLY to the eye to treat INFECTION, ALLERGY, GLAUCOMA, and during the OCULAR EXAMINATION
the choice of base and any excipients used for ophthalmic preparations must be proven, through product development studies, not to what?
Adversely affect either the STABILITY OF THE FINAL PRODUCT or the AVAILABILITY OF THE ACTIVE INGREDIENTS AT THE SITE OF ACTION
is the addition of coloring agents recommended for ophthalmic preparations ?
NO. NOT RECOMENDED
Ophthalmic preparations supplied as_____ may include a suitable antimicrobial agent UNLESS______?
Ophthalmic preparations supplied as MULTIDOSE PREPARATIONS may include a suitable antimicrobial agent UNLESS THE ACTIVE INGREDIENT ITSELF HAS ANTIMICROBIAL ACTIVITY
The antimicrobial activity in ophthalmic preparations should remain effective for how long?
Should remain effective throughout the entire period of use
Name the different categories of ophthalmic preparations
Drops consisting of EMULSIONS, SOLUTIONS, SUSPENSIONS, AND OINTMENTS
what is the capacity of the eye ?
5-10 microliters
For most droppers, 1 drop measures about….
50 microliters
As mentioned, the capacity of the eye is 5-10 microliters. For most droppers, 1 drop measures about 50 microliters.
What can you conclude from this?
The excess solution that the eye cannot hold is quickly flushed away within a couple of minutes.
WHY is drug absorption through the eye very limited?
Due to the thickness (several layers) and composition of corneal and scleral tissue.
Only a small fraction of drug applied is absorbed through eye tissue
WHY are viscosity-enhancing agents included in ophthalmic preparations?
- To decrease the frequency of administration
- Increase the corneal contact time
What is a downside to adding viscosifiers to ophthalmic preparations?
May cause blurry vision
What is added to eye formulations for their soothing and emollient action?
Lubricants
Give an example of a lubricant used in ophthalmic preparations
Hydroxypropyl methyl cellulose
True or false
Ophthalmic preparations must be prepared in a sterile environment
TRUE
Opthalmic solutions must contain ____ to maintain sterility
Preservatives
Name 4 common opthalmic preservatives
-chlorobutanol
-phenylmercuric acid acetate
-thimerosal
-benzalkonium chloride
Benzalkonium chloride concentration in eye preparations is ____%
0.01%
Function of EDTA
Chelating agent
What 2 things are used together in eye preparations to increase effectiveness against the pseudomonas bacteria ?
EDTA and benzalkonium chloride
Ideally, the pH of opthalmic drugs should be ____
Physiologic pH (7.4)
The pH and buffering agent selected for opthalmic formulations should be optimal for both the —— and ——-
For both the STABILITY OF THE API and the PHYSIOLOGICAL TOLERANCE
When 1-2 drops are added to the eye, what adjusts the pH enough to prevent any kind of discomfort ?
THE BUFFERING CAPACITY OF THE LACRIMAL FLUID
When a buffer system is used in opthalmic formulation, it must not cause ____ or ____ of the active ingredient
Precipitation or deterioration
For ophthalmic preparations, pH range of _____ is acceptable
4-9
Is atropine sulfate an acidic or basic drug?
Basic
Basic drugs are usually UNSTABLE at _______ (higher or lower) pH and may precipitate out of solutions
Higher
True or false
Only active ingredients contribute to osmotic pressure
FALSE — both active and inactive ingredients contribute
Ophthalmic solutions are made isotonic using _____ and _____
Sodium chloride and boric acid
The amount of boric acid required to maintain isotonicty of opthalmic preparations is calculated how ?
Using sodium chloride equivalents
Name the 6 routes used for injections
-intravenous
-intramuscular
-subcutaneous (into skin)
-intradermal (just beneath the dermis)
-intrathecal (in spinal cavity)
-intra-arterial
What is unique about injections ? What can you conclude from this ?
They skip the natural defense systems and are delivered directly into the body
Therefore, they must be prepared with great care to prevent infection and toxicity
Injectable and sterile irrigation solutions must be _____ free. Explain why
Pyrogen
Pyrogen is a metabolic byproduct of living microorganisms. In humans, pyrogens cause febrile (fever) reactions and cutaneous vasoconstriction
How are pyrogens removed from opthalmic preparations ?
By treating with chemicals OR with the use of heat (250 degrees Celsius for at least 30 mins)
True or false
Injectable solutions can be made up of both aqueous and non-aqueous solvents
TRUE —- all dependent on solubility and stability of the active compound
Name 3 commercially available non-aqueous injectable formulations
-cyclosporin
-lorazepam
-haloperidol
STERILIZATION means….
The destruction of ALL living organisms AND spores or their complete removal from the preparation
Name the 5 general methods used to sterilization
-moist heat or steam
-dry heat
-filtration
-gas
-ionizing radiation
The sterilization method is selected based on what?
The nature of the ingredients and the method of preparation
True or false
Sterilization method chosen MUST be compatible with the stability of the ingredients and at the same time assure sterility
TRUE
What is generally the sterilization method of choice ? Why? Explain how it works
Moist heat sterilization is generally the chosen method because it is the MOST EFFECTIVE and requires LOWER TEMP THAN DRY HEAT STERILIZATION (121 degrees Celsius for 20-30 mins vs 150-170 degrees Celsius for at least 2 hours)
Filtration method of sterilization is used for ________. How does it perform its task?
Filtration is used for SOLUTIONS and it physically removed the microorganisms from the solution
Filtration method of sterilization uses a filter with a pore size of _____
0.2 microns
Filtration method of sterilization uses a filter with a pore size of 0.2 microns.
What can you conclude from this?
It will filter out most bacteria but is not suitable against viruses
Name 3 ways in which the manufacturing area is maintained sterile
-using UV light
-filtered air supply
-sterilizing all sterilizing equipment and glassware befor use
True or false
Rigid aseptic procedures are required to assure sterility
TRUE
———— are designed to prevent microbial and particulate contamination in the workspace
LAMINAR FLOW HOODS
Explain how laminar flow hoods work
Provides a steady stream of filtered sterile air that pushes out any microbial and particulate contamination from the workspace.
The air stream flows vertically in a vertical laminar flow hood (protects the user) and horizontally in the horizontal laminar flow hood
Provides an aseptic work area and contains the infectious splashes or aerosols generated during preparation
