Ocular Intro Flashcards
If you are having a Anaphylactic reaction what should you do?
This will lead to obstruction in airways
Should care with EPINEPHRINE
1) IV Steroids
2) O2
3) Intubation - insert a tube to the airways
4) Airway management
What is FDA REQUIREMENT FOR Drugs?
90% have to be active
>18 mo shelf life
Antimicrobial preservation vs non preserved until dosing vials
What are the routes of Injection?
1) Sub-junctival
2) Intra-cameral
3) Intra-veitreal
4) Peri-bulbar
5) Retro-bulbar
6) Subtenon’s
In what case and what drugs would you use SUB-TENON’S for the injection?
If you have EDEMA, UVEITIS, and Post cataract Surgery
Use : Steroids
In what case and what drugs would you use SUBCONG for the injection?
Lower dosage High local concentration*** No compliance concerns Useage: Severe corneal disease ex. Treating bacterial ulcer or using 5 FU post trabeculoplasty
In what case and what drugs would you use Intracameral for the injection?
Visco elastic for glaucoma filtration and cataract surgery to protect corneal endothermic and anterior chamber collapse
1% Post OP LIDOCAINE for comfort at ciliary body iris
In what case and what drugs would you use INTRA-VITREAL for the injection?
Endopthalmitis with subconj injection Retinitis ex. cytomegalovirus Triamicnolone for diabetic macular edema Antiangiogenic inserts for macular degeneration's
In what case and what drugs would you use PERIBULBAR for the injection?
Anesthesia and Akinesia
- Slower than retrobular injection
- Considered safer alternative from early days
In what case and what drugs would you use RETROBULBAR for the injection?
Into the muscle cone
- High penetration risk
Much lesson common today than early days
What chemical class does EDTA belong to?
Chelators (metals )
They bind to heavy metals
What are chemical toxins? and what are the types?
ALCOHOL
HEAVY MEALS
Bacteriostatic
Which ones are Bacteriostatic?
PROVIDONE (PVP)
- – This is a water soluble synthetic
- Non ionic polymer
- Absorbs 40% its weight in water
- Used in WWII as plasma expander for trauma
- It complexes with iodine, mercury, nicotine, cynanide
- *** it reduces their toxicity but preserves bactericidal action
Which ones are mercury based?
Thimersol
- Used in CL solutions in early days
- – Toxicity caused reactions
- then they found dilution of this that can reduce the toxicity
- Still used in VET products
What is often combines with EDTA?
Chlorobutanol
- Less allergenic than benzalkonium chloride
- When combined with alcohol it will be a potent preservative
What are PRESERVATIVE SURFACTANTS?
Biguanides
Quaternary Ammonium compounds
What drugs are includes under Biguanides?
PHAMB
PAPB
Chlohexidine
Alexidine
What are quaternary Ammonium compounds?
Benzalkonium Chloride (BAK)
Polyquaternium (Quats)
PQ-1 (polyquad)
PQ-10
What does the Ammonium compounds do to the cell membranes?
Cationic surfactants are ammonium containing molecules that disrupt cell membranes and destablize enzyme structure and function
— anionic solutions mixed with cationic surfactants will inactivate them
whats good about Cationic surfactants compared to anionic surfactants?
Cationic surfactants are less toxic to the ocular surface owning to ineractions with the negatively charge corneal cells
What is Poly-amino-propyl-buguanide forumated as?
1ppm DYMED Baush + Lomb
Whats the advantage of Chlorhexidine?
2 separated plus charges and less membrane intercalation compared to BAK
What is advantage Alexidine?
it is similar chlorhexidine and that has ehtylhexyl end grps making it more BACTERCIDAL
Whats so convterversioal about BAK?
it has 0.01% reduces TBUT by 50% through corneal epithelial toxicity, thts why using this product on artifical tears is controversial
What are drugs that included in OXIDANTS category?
Sodium perborate
= this is inactivated pH sensitive and questioned in use on dry eyes
Metabolized frm hydrogen peroxide to water and oxygen
Sodium Chlorite
== Light inactivated
= Convertes it to water and Sodium
What drugs are included in sodium Perborate?
Genteal (gen aqua)
Thera Tears
What drugs are included in Sodium chlorite?
Allergan Refresh (Purite)
Blink
Brimonidine (purite)
Why Brimondine with purite is better choice?
it is more pH neutral and absorbed better than higher preserved formulations
What are Preservative Free (PF) drugs?
Artifical tears Cyclosprine Timolol Zioptan Ketoralac Cosopt- PF
What are Self preserved drugs?
Moxifloxacin 0.5%
Can you reuse PF?
YES as long as they are recapped, can be used over 12hr period
What is the Yellow eye drop cap means?
Beta Blockers
What is the Dark Blue eye drop cap means?
Beta blocker combos
What is the RED eye drop cap means?
Mydriatics and Cycloplegics
What is the DARK GREEN eye drop cap means?
Miotics
What is the ORANGE eye drop cap means?
Carbonic anhydrase inhibitors
What is the GRAY eye drop cap means?
Non steroidal anti-inflammatories
What is the PINK eye drop cap means?
Steroids
What is the TAN eye drop cap means?
Anti-infectives
What is the TEAL eye drop cap means?
Prostaglandin analogs
What is the PURPLE eye drop cap means?
Adrenergic agonists
Define Affinity
The ability of the drug to bind to receptor
** greater affinity means you need less concentrations than with less affinity**
Receptor
binding site with a biological effect; can be bound to a membrane or floating around
Intrinsic activity
capacity to produce a biological effect
Define o Agonis
Have INTRINSIC affinity and Affinity
Define Antagonist
Have affinity but NOT INTRINSIC,
NO biological effect, no ED50 or EC50,
Efficacy = 0
Allostery
a bound ligand influences specificity at another site
Efficacy
affinity x intrinsic activity
Dose INDEPENDENT
EC50
Effective concentration at 50% of subjects
once the drug in the body, how much concentration must be present in order to get the effect on the body
ED50
Effective dosage at 50% subjects
How much drug is given into the body, only part of it will reach the blood and some of it will be eliminated
IC50
inhibitory concentration at 50% of subjects
Hypersensivitiy
Result of chronic antagonism
Maximum dosage
Using minimum amount of dosage to get the maximal therapeutic effect so we will not run into any toxic effects
o Partial agonist:
low intrinsic activity with potency and affinity within the therapeutic range
It has lower capacity to produce the desirable biological effect
o Pharmacodynamics:
the drugs action on the body, biochemical and physiological effects of drugs and their mechanisms of action
- Pharmokinetics
the body’s action on the drug (ADME)
- Absorption
- Distrubition
- metabolism
- Elimination
o Pharmacotherapeutics:
drugs action on the target disease
o Potency
response to a given dose; less dose to present the same effect means the drug is more potent;
Potency and EC50 are inversely related in agonists
Potency and IC50 are inversely related in antagonists
Specificity
ability to act at a specific receptor; side effects occur when a drug does not have a high degree of specificity
Selectivity
The ability to give desired effect vs adverse effects
Therapeutic Index
LD50:ED50
Lethal dosage = on animals
Higher the therapeutic number the safest ***
ED50: TD50
what is Tachyphylaxis
rapidly decreases the therapeutic response
Teratogenesis
Congenital malformation
Bioavailability
Amount of active drug that is reaching target tissue
What is supplemental?
When you are taking additional vitamins since you are not making them
Ex. insulin
What is supportive?
when you are helping to RELIEVE the symptoms but do not cure the problem
ex. Glucose
What is PROPHYLACTIVE
You are preventing the sympptoms
Ex. low dosage of asprin
What is Symptomatic
You are TREATING The symptomatics, but not the problem
ex. histamine allergy drops
ex. olopatadine
Diagnostic
Dilating drops
ex. fluoresecine drops to figure out whats wrong
Therapeutic
has effects deep within the cell, produces many changes and can be seriously toxic if not closely monitored
What are the 4 superfamilies?
ION CHANNELS
Cacium release
