Aerosols Flashcards
When we say deep lung inhalation, this means….
to the alveoli where there is a huge surface area
Propellants are used to…..
break the formulation into mist
What type of particles are required to reach the deep lung?
aerodynamic diameter
route of inhalation (4)
trachea–> bronchi–>bronchioles–>alveoli (tiny sacs)
aerodynamic diameter is also known as
mass median aerodynamic diameter (MMAD)
There are ____ and _____ factors that affect particle deposition
pharmaceutical
physiological
Factor: pharmaceutical vs. physiological
- size
- density
- shape
- charge
pharmaceutical
Factor: pharmaceutical vs. physiological
- breathing pattern
- vasculature
- lung anatomy
physiological
Factor: pharmaceutical vs. physiological
- mucociliary clearance
- coordination of aerosol generation and inspiration
physiological
Factor: pharmaceutical vs. physiological
- velocity
- device
- pattern
- dose
- drug properties
pharmaceutical
advantages for inhaled drug (4)
- rapid onset
- huge surface area due to alveoli
- reduce dosage and side effects
- avoid first pass metabolism
What do aerosol depend on for power to disperse the active ingredients in a mist, foam, or semisolid? (2)
liquefied or compressed gas
The _____ and _____ are an integral part of the formulation for aerosols.
valve assembly
propellant
What does the particle size control for aerosols?
the site of action bigger particle (localized effect in trachea) to smaller particle (alveolar ducts and alveoli)
liquefied vs. compressed gas
liquefied: more powerful expansion power (broken up into fine mist)
compressed: more coarse/wet particles
T/F You DO need liquefied gas for semisolid aerosols
FALSE; do not
T/F There is no contamination of residual product; sterility is maintained without preservative
TRUE
T/F Dosage is controlled by metering valves in some aerosols
TRUE
What is the story behind fluorinated hydrocarbons?
best for deep lung delivery, but they damage the ozone layer
extremely effective, relatively inert, nontoxic, and nonflammable
Types of aerosol propellants? (2)
- hydrocarbons
- compressed gas (do not give fine mist)
What will happen to the pressure in an aerosol container as some product is released?
- liquefied propellant is used: pressure remains constant
- compressed gas is used: pressure decrease because gas amount decreases
Types of aerosol filling (2)
- cold filling
- pressure filling
When can cold filling be used?
product first then valve
-if it’s a known aqueous solution
Which filling is most common in pharmaceutics?
pressure filling
-valve first then product
______ of propellant exerts pressure in all directions
vapor pressure
_____ this pressure forces the liquid up the dip tube and out the valve orifice
upon actuation of valve
________ propellant vaporizes to break the formulation into a fine mist
upon release
What controls the pressure/type of aerosol? (3)
- type and amount of propellant
- product concentrate
- valve
What happens when a drug is not mixable with the propellant?
it will break out into layers
types of aerosols? (4)
- space spray
- surface spray
- foams
- inhalation aerosols
types of aerosol?
- a lot of propellant
- high pressure
space spray (ex. deodorizer)
types of aerosol?
dermatological spray
surface spray
types of aerosol?
emulsion
foams (ex.shaving cream)
types of liquid inhalers? (2)
- metered dose inhaler
- nebulizer
metered dose inhaler
-defined dose given (limited volume discharge)
nebulizer (2)
- no propellant instead have compressed air (used to break the drug solution into fine particles)
- valve attached to external pump
T/F CFC free MDI are available
TRUE
A metered dose inhaler is designed to deliver an asthma medication-does it have to be sterile? Will it be single or multiple dose? preservative? How about a nebulizer?
- YES because it is going into the lung system (lung is a delicate organ)
- Multiple with no preservative due to positive pressure
- Yes sterile, but no preservative due to external pump; single dose
T/F Dry powder inhalers can deliver drugs to deep lung
TRUE
What is an advantage of dry powder inhalers?
aerosol particles contain drug in very concentrated form allowing deliver of therapeutic dose in one or three puffs
T/F Risk of microbial growth, which can cause lung infections, is LESS in liquids than in solids
FALSE: greater
Aerosolization generates excessive air/water interface….
may lead to denaturation or aggregation (evaporation of droplets may cause increase in protein concentration)
What is purpose of spacer?
to give the particles a longer time to break down before it gets to the mouth
