Heather

Question 1

Advantages of Nasal administration

Answer 1

• large SA
• highly vascular
• avoids first pass
• accessible

Question 2

disadvantages of Nasal administration

Answer 2

• muscus clear foreign things quickly
• highly enzymatic activity
• large MW has low bioavilability
• ciliated epithelium is easily damaged

Question 3

examples of nasal delivery

Answer 3

small peptide
-calcitonin 
-desmmopressin
local treament
-xylometazoline 
budesnoide
system absorption
-sumatriptan

Question 4

what affects Nasal delivery?

Answer 4

MW
partition coeffecient
solubility and dissoultion rate
volume 
and concentration 
viscosity
droplet size

Question 5

advantages of ocular delivery

Answer 5

easy

• not invasive
• good patient acceptance

Question 6

disadvantages for ocular delivery

Answer 6

Corneal epithelium is a barrier - prevents fluid getting in
poor bioavailability
short duration - removed via lacrimal fluid
-can be systemically absorbed via conjunctival stroma
-ineffective for posterior of eye
-must be given frequently at high doses

Question 7

What is photodynamic therapy? (PDT)

Answer 7

• treatment for choridal neovascular membranes
• new blood vessels that grow under retina, when they leak = blindness
• IV dye called Visydyne is given
• then give red laser (689nm) for 90 secs
• activates the dye
• inhibits growth of blood vessels

Question 8

What is Intraocular drug delivery?

and barriers

Answer 8

• placing a drug delivery system in the eye
• continuous drug admission
• CR 7 days -1 year
• Blood-aqueous barrier - non-pigmented layer of cillary, controls inward movement
• Blood-retinal barrier - retinal pigment epothelium, controls outward movement

Question 9

advantages and disadvantages of systemic administration of eye medication

Answer 9

ad: more effective for posterior eye problems
dis: most drugs dont pass blood-ocular barrier, systemic side effects

Question 10

Ocular inserts

• about
• erodible
• non-erodible

Answer 10

• no change to vision or O2 permeability, comfort, ease, sterile, stablity
• do not remove, collagen or chitosan, patients tear turnover
• unsure if fallen out ect ect
• more consistence, contrl of drug release, discomfort, pilocarpine insert

Question 11

How dose pilocarpine ocular insert work?

Answer 11

• non-erodible
• sandwiched between two ethylene-vubyl acetate membranes. Alginic acid matrix as drug reservoir
• annular ring allows patient to see it
• it float in tears
• leave in for 7 days

Question 12

Advantages and disadvantages of eye injections

Answer 12

ad: improve adsorption, delivery to posterior of eye, no systemic effect
dis: short half life, pain, discomfort, infection risk, poor acceptance, may increase toxicity risk

Question 13

Advantages and disadvantages of ocular implants

Answer 13

ad: increase half life, by pass blood ocular barriers, less side effects, constant drug levels, less drug required
dis: invasive, complications, survery to remove if non-biodegradable , may ‘burst’ at end releasing a lot of drug
- eg scleral plug

Question 14

Advantages and Disadvantages of Implants

Answer 14

ad: compliance, controlled release, prolonged
dis: surgical implant, sterility, cost

Question 15

Alzet Osmotic pumps

Answer 15

clever capsules

• body fluid enters cap
• dissolves osmotic layer
• increases volume, increases pressure
• forces drug out

Question 16

Implanton NXT

Answer 16

• progestion 68mg
• suppression of oluvation and increase muscus thickeness
• 3 years 99.9%
• drug release rate changes over 3 year period

Question 17

Testopel (Endo)

Answer 17

sub/cut
pellets contain 75mg of testosterone
lasts 3-6 months