ipph exam 2 flash cards.txt

• o Maintenance of optimum drug concentrations
• o Improved efficiency of treatment with less amount of drug
• o Minimized side effects
• o Less frequent administration
• o Increased patient convenience and compliance (adherence)

• o Relatively high production costs
• o Leakage of drug mass (dose dumping)- all dose is accidently released at once
• o Difficulty of stopping drug release
• o Necesssity of surgical operation (sometimes)
• o Biocompatibility of the controlled-release device (body wants to get rid of foreign objects)

• " Drugs with a long half-life
• " Drugs which long-term effect is undesirable
• " Drugs which require immediate effect

• " Diffusion-controlled systems
• " Dissolution-controlled systems
• " Erosion-controlled systems
• " Osmotic systems
• " Mechanical systems
• " Swelling systems

diffusion reservoir system

diffusion reservoir system

diffusion reservoir system

Osmotic system

erosion controlled system

erosion- controlled system

erosion- controlled system

The most hydrophilic polymer degrades the fastest" Lower molecular weight polymers degrade fastest

erosion- controlled system

Goblet cells or specialized glands

glycoproteins, lipids, inorganic salts, and 83% water

<1 micrometer to 450 micrometers

Mucus protects the mucosa in the stomach from HCL. It keeps the mucosal membrane moist. It is also a diffusion barrier for drugs.

Mucin is a protein that contains many systeines which are capable of forming disulfide bonds. It also has sialic acid which has a negative charge. It is a very long molecule.

Mucoadhesion can occur by charge interaction between a positive polymer and the negative mucus. It can also be because of covalent bonding between a thiolated polymer and cysteine-rich mucin. Hydrogen bonding and polymer interpenetration can also cause mucoashesion.

• " Drugs delivered via oral mucosa are predominantly lipophilic. They are mostly small in molecular weight. They also may require absorption enhancers to deliver hydrophobic molecules
• " More lipophilic polymers are better absorbed

" The tablet should be placed between the cheek and the gum and not bitten, chewed, or sucked

• " Bioavailability is less than 10%
• " There are barriers which are hard to penetrate (cornea, blood-retina barrier)
• " Loss due to dilution in the tear film, fluid spillage, drainage
• " Short residence time: rapid turnover of tears and aqueous humor
• " Not much flexibility in formulation (pH, osmolarity, solubility)

" Ocular implant is loaded with human retinal pigment epithelium cells transfected with CNTF gene to produce CNTF in situ. This uses bodily nutrients to produce proteins to retard retinal degeneration caused by retinitis pigmentosa

Respiratory region

it allows for systemic drug delivery

It is responsible for humidification and warming of inhaled air occurs. Physical and enzymatic protection against foreign compounds (including drugs). Mucus sticks to inhaled particles or pathogens and lets them be removed by mucociliary clearance.

Blood brain barrier

driven by momentum; increase with particle velocity, diameter, density; upper airways

bypassing the BBB via olfactory epithelium and olfactory bulb.

particles greater than .1 micrometer; increase with diameter and density

ultrafine particles less than .1 micrometer; lunch periphery; tent tp be exhaled without depositing

• " Vt: Terminal settling velocity
• " p: densities of particles
• " g: acceleration due to gravity
• " D: volume diameters
• " C(D): slip correction factors
• " k: shape factors
• " n: viscosity of fluid (air)
• " Diameter
• " Density
• " Shape (fibers, elongated particles, needles, spheres)

" Geometric diameter (Dae) of a particle with a unit mass density (1 g/cm3) that would settle at the same velocity as the particle of interest

the defense mechanisms of the lung

• o Filtering mechanisms in the nasal cavity trap and eliminate large particles (>10micrometers)
• o Reflexes: sneezing and coughing

o Mucociliary escalator, IgA (produced by plasma cells in the submucosa)

• o Alveolar macrophages with some interplay with and by neutrophils
• o Immunologic mechanisms: interplay between the alveolar macrophages and T &B lymphocytes; IgG

- a small volume of pressurized drug dispersion is isolated in a metering chamber and then released through a spray orifice. As the released drug dispersion begins to equilibrate with the atmospheric pressure, it is propelled from the container forming a spray of droplets. Composed of drug, propellant, cosolvent, and surfactant.

generate droplets of a drug dispersion (usually aqueous solution or suspension) using energy from compressed air or piezoelectric ceramics. Delivered to the patients lungs on their inspiratory flow. Suitable for treatment f young and elderly patients and emergency treatment.

collection of dry particles contained in an inhaler device. An aerosol of dry powder is created as it is exposed to inspiratory airflow, which then carries the small drug particles to the lung. Depending on the inspiratory flow rate, the dose deposited in the lung ranges from 5-40%.

• " Ordered mixture
• " Co-spheronization
• " Large porous particles

Whole body or nose only exposure chambersoInstillation or insufflationoGamma- scintigraphy, single-positron-emission computer-aided tomography: to estimate the site of deposition of drugs.

• oAnderson cascade impactor
• oNext generation impactor
• oLiquid impinger

b) a plasticizer

d) rubbery

d) Nylon was synthesized based on the theory on polymeric nature of plastics.

a) Low temperature

b) High temperature (e.g., 37 �

c) They can control the diffusion of molecules by simple altering of the polymer structure or concentration.

d) More frequent administration

b) A membrane that allows diffusion of water molecules but not other bigger molecules.

d) Diffusion-controlled monolithic system

b) Diffusion-controlled system

d) The drug release rate is independent on both pH and temperature.