3 Barriers of the eye:
- Blood retinal
- Blood Aqueous
- Blood Vitreous
Tears are composed of:
- Mucin Mixture
- (=> Tear Film)
Which layers are hydrophobic/phillic?
- Epithelial Layer= phobic
- Stroma= philic
- Corneal Endothelium= phobic
What variable property of the eye => increased binding
What type of nerves innervate the sphincter smooth m in the anterior chamber?
Parasympathomimetic drugs =>
What can cause opacity of the lens?
- Drugs (glucocorticoids)
- Dz (Diabetes M)
Where can passage of drugs occur inward or outward via BVs?
Target for Tx of Glaucoma
Tx for optical neuritis:
Which admin route will => rapid absorption?
What are intravitreal injections/devices used to Tx?
In General, what pathways/routes do drugs enter systemic circulation?
What are the 3 types of formulations?
- Gels/Ointments/Solid Inserts
Which formulation=> prolonged time on eye surface?
What determines absorpton after topical admin?
- Time in cul-de-sac/precorneal tear film
- Elimination by Nasolacrimal Drainage
- Binding to tear proteins
- Metab by tear/tissue proteins
- Diffusion across cornea/conjunctiva
What pathways allow TOPICAL drugs enter systemic distribution?
- Nasal Mucosal
- Local (Conjunctiva-Cornea)
- Transcorneal:accumulation in aqueous humor
Metabolism within the eye occurs by
- Enzymatic biotranformation (Esterases)
- Systemic Biotranformatio (Liver/kidney)
Therapeutic Targets of Opthalmic Drugs:
- Non-Infectious (trauma, immune, +P, etc)
- Symptomatic (Pain)
- Diagnostic (Local Anesth, Dyes, etc)
Most Bacterial Infections are caused by.... (G+/-)
- Dogs: G+
- Cats: G+ & G- RARE
- Horses: G+ & G-
- Cattle: G- & G+
infections in dogs are caused by which organisms?
infections in cats are caused by which organisms?
- Myco. Felis
- (Chlamydia felis, rare)
infections in horses are caused by which organisms?
- Strep Zoo
- Pseudomonas (-)
Tx for Conjunctivitis
- Polymixin B
Tx for blepharitis (5):
- Polymyxin B
Tx For Keratitis:
- Polymyxin B
Which Drugs have ++ distribution?
Which can't be used in food animals?
Frist choice for ulcers and conjunctivitis?
Groups of anitfungal opthalmic drugs:
- Nucleoside Analogs
Broad Spectrum antifungals:
- Amphotericin B
- Itraconazole (+DMSO)
Focus of glaucoma Tx:
- Decrease production of Aqueous Humor
- Increase Outflow
What types of drugs are usde to Tx Glaucoma?
- Topical prostaglandin analogs
- B Adrenergic Antagonists
- Carbonic Anhydrase Inhibitors
- Topical Mydriatics
Mechanism of topical prostaglandin analogs in Tx of Glaucoma
Facilitates Outflow via uveoscleral pathway
Mechanism of B-Adrenoreceptor anatgonists in Tx of Glaucoma
Regulates aqueous humor production
What type of drug is latanoprost?
topical prostaglandin analogs, for glaucoma
What type of drug is timolol maleate?
B Adrenoreceptor antagonist
Topical Anti-inflammatory drugs
- Cyclosporine A
- Proparacaine & Tetracaine
- Lidocaine & Bupivicaine (infiltration)
2% povidone iodine