Lab 10 Flashcards
nasal solutions are administered in the nose or nasal cavity as what 4 dosage forms?
-drops
-sprays
-inhalations
-nebulizing solutions
where are nasal preparations administered?
in the nose or nasal cavity
nasal solutions are most commonly used topically for a ____ (local or systemic?) effect
local
explain how it is possible for nasal preparations to give systemic effects and give an example of an intranasal product that gives these systemic effects
the nasal mucosa is an excellent absorbing surface
insulin
nasal solutions for INHALATION and NEBULIZATION are designed for delivery to……
the respiratory tract
true or false
nasal preparations should be sterile when dispensed
true
nasal ____ containers MUST contain preservatives to prevent the growth of microorganisms
MULTI DOSE
When selecting the preservative for a nasal multi-dose container, what factors should be considered?
-compatbility with other ingredients
-pH of the preparation
what can you say about the pH of nasal solutions
these solutions must be adjusted to the pH of normal nasal secretion (5.5-6.5)
strong buffers outside pH 5.5-6.5 are not used in nasal solutions
WHY
nasal secretions have a poor buffer capacity
what can you say about the osmotic pressure and tonicity of nasal preparations
nasal cilia can TOLERATE a tonicity of 0.5%-2% of sodium chloride
however, solutions applied to mucous membranes (such as nose and eyes) MUST BE MADE AS CLOSE TO ISOTONIC AS POSSIBLE (0.9% sodium chloride)
Tonicity greater than 4% and less than 0.3% NaCl are HARMFUL to the nasal mucosa
the cilia in the nasal passages are sensitive to…..
OSMOTIC PRESSURE
What is the most common solvent for nasal solutions?
water (though other solvents with known safety for internal use can be used)
name 6 types of excipients which nasal solutions contain
buffers
tonicity agents
preservatives
antioxidants
surfactants
viscosity-inducing agents
nasal solutions are commonly used to relive symptoms of…..
common cold
sinusitis
hay fever
other upper respiratory tract allergies
explain what decongestants are and how they accomplish their purpose
adrenergic (sympathomimetic) drugs that REDUCE CONGESTION by constricting the blood vessels in the nasal mucosa
this constriction of blood vessels results in them shrinking and draining, thus improving ventilation (breathing) and stuffy feeling
explain a bad side of topical decongestants
they may damage the nasal mucosa when used for long periods. therefore, they should not be used for more than 2-3 days
some decongestant nasal solutions contain SULFITES that cause life-threatening or less severe asthma in certain susceptible people
true or false
systemic side effects cannot be observed when using nasal solutions
FALSE —
systemic side effects CAN be observed when using nasal solutions because the nasal mucosa is a good surface for absorbing drugs
since systemic side effects can be observed when using nasal solutions, in which populations should they be used with caution?
patients with THYROID and CARDIOVASCULAR disease
true or false
elderly patients 62 years and older are more likely to experience the adverse effects of nasal preparations
true
true or false
some individuals may experience mild and transient burning sensation after applying topical solutions
TRUE
the nasal cavity is a large, ___ -filled space above and behind the ____ in the middle of the face
the nasal cavity is a large, AIR-filled space above and behind the NOSE in the middle of the face
the blanket of mucus that covers the nasal fossae lies superficial to the ____ and serves what function?
superficial to the microscopic cilia.
function = filter inspired (inhaled) air
the mucous membrane is the thickest and most vascular over which structure?
where is it second-most thick?
THICKEST over the nasal conchae
second most over the septum
where is the mucous membrane very thin?
on the meatuses on the floor of the nasal cavity, and in the various sinuses
what is one of the most commonly infected tissues in adults and humans?
nasal tissues
inflammation of the nasal tissue can cause…
significant impairment of daily activities.
symptoms: stuffy nose, headache, mouth breathing
epinephrine requires ______and appropriate __ and ___to maintain its stability.
explain
epinephrine requires ANTIOXIDANTS and appropriate pH and storage to maintain its stability.
why antioxidant? epinephrine undergoes autoxidation
what pH? increasing pH causes epinephrine oxidation and can decrease its biological activity
Epinephrine is not compatible in _____ and other ___ solutions and drug mixtures
epinephrine is not compatible in SODIUM BICARBONATE and other ALKALINE solutions and drug mixtures
(oxidizes more easily in high pH)
what color is epinephrine when it gets oxidized?
red
isotonicity is expressed in terms of ______. (___ or ____)
OSMOTIC PRESSURE (osmolarity or osmolality)
isotonicity depends on….
the number of particles of solute in solution
osmotic pressure is ______ proportional to the degree of dissociation
DIRECTLY
When sodium chloride is 100% dissociated, it will have ______ particles for every _____ of NaCl
2 PARTICLES FOR EVERY MOLE
If the substance is partly dissociated (not 100%), how is osmotic pressure calculated?
using the dissociation factor
blood and other body fluids has the same osmotic pressure as….
a 0.9% w/v solution of NaCl
Sodium chloride 0.9%w/v solution is said to be _____ with blood
isotonic
what are hypertonic solutions?
what are hypotonic solutions?
hypertonic solutions – have a higher osmotic pressure than body fluids
hypotonic solutions – have a lower osmotic pressure than body fluids
non-isotonic solutions can damage _____ (especially ________)
non-isotonic solutions can damage TISSUES, especially MUCOUS MEMBRANES
Preparations meant to be applied to THESE DELICATE TISSUES must be made isotonic
-nasal
-eye
-parenteral
the “sodium chloride equivalent of a substance” is defined as…..
the amount of sodium chloride (in grams) that has the same osmotic pressure as 1 gram of the substance
the sodium chloride equivalent of a substance is symbolized by what?
the letter E
what is the most frequently used method in calculating the amount of sodium chloride needed to prepare isotonic drug solutions?
the sodium chloride equivalent method (using E)
what does sterile mean?
free of all microorganisms
when MUST preparations be sterile?
-when there is a possibility of infection
-when they are instilled directly into body tissues and cavities — this bypasses the natural defenses of the body
name 5 sterile products
-nasal
-ophthalmic
-injectables
-hemodialysis
-irrigation solutions
_____ and ______ must ensure sterility
quality of ingredients and methods of preparation
when must preservatives be used?
for SMALL VOLUME and MULTIDOSE preparations – to prevent microbial growth (called proliferation)
preservatives are not used in which sterile preparations and why?
not used in LARGE VOLUME sterile preparations (like IV fluids)
bc a large quantity of preservatives is required to preserve this large volume — causes toxic effects
all sterile preparations are prepared where?
all sterile preparations are packed in what?
all sterile preparations are prepared in a STERILE ENVIRONMENT
all sterile preparations are packed in STERILE CONTAINERS using ASEPTIC techniques
what does “particulate free” mean
free of all visible particulate material
product is filtered to obtain a clear solution before packaging it.
sterilization by filtration will also remove the particulate matter
when preparing sterile products (ophthalmic, nasal, injectables, hemodialysis, irrigation solutions) which FIVE THINGS MUST BE ENSURED
-sterility
-particulate free
-stable
-pH
-isotonicity
sterile products must be stabilized how?
why?
using antioxidants and other appropriate ingredients
this is done to maintain EFFECTIVENESS OF THE ACTIVE INGREDIENT AND THE FORMULATION
sterile solutes must be _____ in the solvent
completely dissolved
the pH of MOST sterile products is generally similar to…..
physiological pH (7.4)
(but varies based on the type of preparation and ingredients used)
nasal preparation pH is btwn 5.5-6.5
most tissues can tolerate solutions having similar tonicity as ____ to ____% sodium chloride.
however, pharmaceutical solutions…….
most tissues can tolerate isotonicity 0.5%-2% sodium chloride.
however, pharmaceutical solutions MUST BE MADE ISOTONIC TO BLOOD AS POSSIBLE to prevent irritation and damage to tissues
When may HYPERTONIC solutions be given?
slowly through large veins bc this allows adequate mixing to minimize the adverse events
