Aerosols Flashcards
Products which depend upon the power of a liquefied or compressed gas to dispense active ingredient/s in a finely dispensed mist, foam, or semisolid
Aerosols
Advantages of Aerosols
- Rapid onset of action
- Prevent first-pass effect, avoidance of GIT degradation
- Minimize ADRs due to lower dose
- Allows dose titration & ideal for prn medication
- Alternate route to prevent chemical & physical interactions w/ other drugs given concurrently
- Useful when oral & parenteral administration is not suitable
Pharmaceutical aerosols intended for administration as fine, solid particles, or as liquid mists via, the respiratory system or nasal passages
Metered Dose Inhalers (MDIs)
Particle Size of MDIs
<10micrometer, usually 3-6 micrometers for maximum therapeutic response
Consists of solutions of active ingrediens in pure propellant & solvents
Solution Aerosols
The active ingredients are suspended or dispersed throughout the propellant/s or propellant & sovents phase
Dispersions or Suspensions (powder aerosols)
Can be dispersed as a spray, stable foam, or quick-braking foam
Emulsions
Depend on nitrogen to push content form package
Semisolid Preparations
Aerosol Systems
Two-phase Systems
1. Liquid Phase (liquefied propellant & product concentrate)
2. Vapor Phase
Three-phase Systems
1. Liquid Propellant
2. Product Concentrate
3. Vapor Phase
Commonly used when referring to the aerosol container or completed product
Pressurized Package
Aerosols used to provide an airborne mist
Space Sprays
Aerosols intended to carry the active ingredient to a surface
Surface Sprays (Surface Coatings)
Agent responsible for developing the pressure within an aerosol container and expelling the product when the valve is opened
Aerosol propellant
Liquefied Gases
- Saturated HC (N-Butane, Propane)
- Chlorofluorocarbons (CFCs) – phased out Dichlorodifluoromethane
- Dichlorotetrafluoroethane
- richloromonofluoromethane
- Dimethy Ether
- Hydorflurocarbons
Compressed Gases
Carbon Dioxide
Nitrogen Gas
Nitrous Oxide
active ingredient of the aerosol combined w/ the required adjuncts, such as antioxidants, surface active agents, & solvents, to prepare a stable & efficacious product
Product Concentrate
Aerosol Container
(a) Tin - plated steel; light & relatively inexpensive
(b) Aluminum - preferred for use w/ most MDIs, strong & less reactive than the other metals
(c) Glass - high aesthetic value & minimal incompatibilities; use is limited to products w/ low pressure & propellant percentage
Most basic part through which the contents of the package are emitted; regulates the flow of product from the container
Valve
Permit expulsion of the contents of the can in the desired form at the desired rate, & in the case of metered valves, in the proper amount of dose.
Valve Assembly
Parts of Aerosol Valve Assembly
Actuator
Stem
Gasket
Spring
Mounting Cup
Housing
Dip Tube
Part of Valve assembly being pressed for emission of the product
Actuator
Part of Valve assembly which supports the actuator & delivers the formulation in the proper form to the chamber of the actuator
Stem
Part of Valve assembly which prevents leakage of contents
Gasket
Holds the gasket in place & is the mechanism by which the actuator retracts when pressure is release, returning the valve to the dose position
Spring
