dosage forms or Preparations of Ophthalmic solutions

Question 1

dosage forms or preparations of Ophthalmic solutions:

Answer 1

Aqueous Solution (eye drops)

Oily Solution

Colloidal solution

Ointment & cream

Dye impregnated paper strip

Ophthalmic disc or tablet (lamellae)

Ocusert

Therapeutic soft contact lens (TCL) or Bandage SCL

Collagen shields

Spray

Question 2

normal Tear volume and (basal tear flow):

Answer 2

7uL

basal tear flow: 1 uL/min

Question 3

Tear volume at cul-de-sac:

Answer 3

20-30 uL

Question 4

maximum bioavailability of eyedrops:

Answer 4

20 uL

Question 5

tear turnover/tear outflow at lacrimal passage:

Answer 5

non-irritated eye: 15% per min

after 1 eyedrop: 30% per min

Question 6

80% of eyedrops egress through ______ not into eye

Answer 6

Tear ducts

Question 7

egress of eyedrops through tear ducts can be decreased with:

Answer 7

punctal occlusion

decrease from 80% to 65%

Question 8

interval before the next eyedrop to prevent egress of the medication:

Answer 8

5-10 mins

Question 9

ways to instill ophthalmic solution (eye drops):

Answer 9

1. Tilt the head back and look at the ceiling
2. Retract the lower eyelid down and away from the eyeball or pinch and retract the lower eyelid
3. Ask the patient to look upward
4. Instill one drop into the exposed cul-de-sac. Be sure the TIP should NOT touch the eyelashes/eyelids
5. Gently close the eyelid for 5 mins

Question 10

ways to prolong contact time of topical solution:

Answer 10

1. Retract the lower eyelids to create a pocket and increase the capacity of the cul-de-sac
2. Close the eyes after instillation for 5-10 mins (DO NOT BLINK)
3. apply pressure on the lacrimal sac
4. Gently massage the eyeball with close eyelids

Question 11

ways to instill ophthalmic OINTMENT:

Answer 11

1. pull the lower eyelid down to create a pocket
2. Place a small ribbon of ointment (about ¼ inch) into cul-de-sac
3. Close the eyelids for a minute
4. Eye massage

Question 12

increases solubility of hydrophilic drugs by altering permeability of corneal epithelial membranes

Answer 12

SURFACTANT

Question 13

determines ionization of a drug

Answer 13

pH

Question 14

ionized portion (water soluble) of solution/drops will be more stable in:

Answer 14

Tears and Corneal Stroma

Question 15

if the pH of the solution is made more basic, it increases:

Answer 15

Lipid solubility and Increases Epithelial Penetration

Question 16

this increases drug contact time on the cornea:

Answer 16

Viscosity

Question 17

a well known contaminants of Fluorescein Dye:

Answer 17

Pseudomonas Aeruginosa

Question 18

known to invade or contaminant of Home made saline solution:

Answer 18

Acanthamoeba

Question 19

added to solutions/eyedrops to prevent contamination:

Answer 19

Preservatives

Question 20

Increases effectiveness of other preservatives:

Answer 20

Chelating Agents (EDTA)

Question 21

Neutral pH of eyes (Tear film):

Answer 21

7 - 7.4 pH

Question 22

since pH of the Tears is slightly alkaline, many ocular drugs are ______

Answer 22

Alkaloids (Weak bases)

Question 23

helps maintain a comfortable pH:

Answer 23

Buffering Agents (weak acid w/ salts)

Question 24

most common Buffering agent:

Answer 24

Boric acid w/ salt

Question 25

relative measure of osmotic pressure between 2 solution:

Answer 25

Tonicity

Question 26

Osmosis is movement of water from ______ to ______ concentration of solute

Answer 26

LOWER to HIGHER

Question 27

ideal Isotonic solution:

Answer 27

0.7% - 1.5% NaCl or 0.6% - 1.8% NaCl

Question 28

hypotonic solution:

Answer 28

\< 0.5% hypotonic

Question 29

Hypertonic solution:

Answer 29

\>2% hypertonic

Question 30

Hypotonic solution is not harmful to \_\_\_\_\_\_eyes it enhances drug corneal penetration but it is harmful \_\_\_\_\_\_\_\_

Answer 30

External eyes to Corneal endothelium (Intraocularly)

Question 31

In KCS _____ solution is given if tears are \_\_\_\_\_\_

Answer 31

Hypotonic Hypertonic

Question 32

5% NaCl reduces:

Answer 32

corneal edema & conjunctival edema

Question 33

10% NaCl causes permanent _______ damage

Answer 33

Corneal damage

Question 34

Classes of Preservatives and example:

Answer 34

Bacteriostatic - Thimerosal Bactericidal - BAK

Question 35

mercuric compound and causes sensitivity and BAND keratopathy

Answer 35

Thimerosal

Question 36

BAK acts as ______ and ______ agent

Answer 36

preservative and wetting agent

Question 37

used with lipid INSOLUBLE drugs to enhance penetration by breaking corneal barrier ex: carbachol

Answer 37

BAK

Question 38

Limited use because it is rapidly destroyed by water Examples of Oily solution:

Answer 38

Diisoprpyl fluorophosphate **DFP**

Question 39

Used for delivery of drugs not readily dissolved in water

Answer 39

Suspension

Question 40

Example of Suspension drug:

Answer 40

Prednisolone acetate

Question 41

made of high viscosity acrylics slow release drug at steady level at overall lower concentration less systemic side-effects

Answer 41

Gel

Question 42

Examples of Gel:

Answer 42

Pilocarpine & Timolol

Question 43

disadvantage of Gel form solution:

Answer 43

Blurring of Vision

Question 44

has semi-solid vehicle which is **lipid soluble** melts when it comes in contact with the eyes

Answer 44

Ointment

Question 45

disadvantage of Ointment:

Answer 45

Increase allergic reaction delay wound healing Blurring of vision

Question 46

semisolid vehicle which is water miscible not applied on cul de sac because it will dissolve by tears & wash out applied on skin of eyelids

Answer 46

Cream

Question 47

examples of cream drug:

Answer 47

Betamethasone

Question 48

used to prevent pseudomonas infection:

Answer 48

Dye Impregnated paper strip

Question 49

rarely used, placed at inferior cul-de-sac

Answer 49

Ophthalmic Tablet or disc (lamellae)

Question 50

preservative free pellet with 5 mg of hydropropyl cellulose used for mucus tear deficiency

Answer 50

Lacrisert

Question 51

small, ovoid, flat of double-layered hydrophilic plastic encloses the active ingredient of Drug

Answer 51

Ocusert

Question 52

Examples of Ocusert:

Answer 52

Pilo 20 - releases 20ug/hr. for 7 days Pilo 40 - releases 40ug/hr. for 7 days (TREATMENT FOR GLAUCOMA)

Question 53

soft contact lens soaked with drugs:

Answer 53

Therapeutic CL - TCL or Bandage SCL

Question 54

examples of TCL:

Answer 54

NSS 5% NaCl

Question 55

similar to TCL except collagen shields slowly dissolves increasing the concertation of drugs w/n the cornea for 1st few hrs

Answer 55

Collagen shields

Question 56

Advantage of TCL and Collagen shields:

Answer 56

1. Act as drug reservoir 2. Increase contact time (prolong effect)

Question 57

disadvantage of TCL and Collagen shields:

Answer 57

Bacteria binds to contact lens - possible ocular infection

Question 58

advantage of Spray as mydriatic or cycloplegic agents:

Answer 58

Less irritation