ROUTES OF OPHTHALMIC DRUG ADMINISTRATION Flashcards
Local acting Ocular drugs:
Topical - solution / ointment / cream
Packs
Iontophoresis
Irrigation
Sustained released device
Target ocular structures of Topical ocular drugs:
Cornea
Conjunctiva
Ciliary body
Anterior segment
systemic route does not penetrate the anterior segment due to presence of?
BLOOD-AQUEOUS-BARRIER
cotton is soaked w/ epinephrine placed at inferior cul-de-sac to prolong its mydriatic effect
Packs
eye-cap bearing an electrode, drug used should bear the same charge with electrode
Iontophoresis - IONS
non-invasive use of medicine ions and charged macromolecules into anterior and posterior segments of eye
penetrating ocular tissues with poor permeability
Iontophoresis - IONS
catheter is inserted at upper eyelids into the cul-de-sac
Irrigation
Indications of Irrigation:
NSS for:
KCS
Chemical corneal burns
Pseudomonas corneal ulcer
examples of Sustained release devices:
PILO 20
PILO 40
drug is injected NEAR the eye (extraocular)
Periocular injections
drug is placed beneath bulbar conjunctiva
Subconjunctival Injection
drug is placed between sclera & tenon’s capsule
Sub tenon’s Injection
drug is placed at exposed sclera
Anterior sub tenon injection
drug is placed at sclera BEHIND equator
can reach the retrobulbar space
posterior Sub tenon injection
drug is injected beneath the globe:
Retrobulbar injection
drug is injected at retrobulbar space only
Anterior Retrobulbar injection
Examples of Retrobulbar injection:
Anesthetic only
anesthesia w/ hyaluronidase
anesthesia w/ epinephrine
retrobulbar injection that produces sensory anesthesia only
Anesthetic only - Anterior retrobulbar injection
anterior retrobulbar injection that produces both anesthesia & akinesia
anesthesia with hyaluronidase
increases contact time by vasoconstriction prevent systemic absorption of drugs
anesthesia w/ epinephrine
Drug is injected up to apex of muscle cone
Posterior Retrobulbar injection
Anesthetic agent only but produces both sensory anesthesia & akinesia
Posterior retrobulbar injection
injection within the globe
Intra-ocular injection
disadvantages of intraocular injection:
Perforation
Hemorrhage
drug injected within aqueous humor
Intracameral injection
indications for Intracameral injection:
Endophthalmitis
drug injected within vitreous chamber
Intravitreal injection
indications for intravitreal injection:
Retinal Detachment
Systemic ocular drugs reaching the globe is dependent on:
Lipid solubility
Plasma protein binding
Molecular weight
Only ______ soluble can pass the ocular barriers
Lipid soluble drugs
only _____ form is bioavailable for plasma protein binding
unbound form
drugs with ________ molecules can pass the ocular barriers
low molecular weight / smaller molecules
Ocular alimentary routes indication:
Antibiotics
Acetazolamide
ocular parenteral routes (IV injections) indications:
Intraocular surgery
endophthalmitis (antibiotics)
acute Angle closure glaucoma
Angiography (ICG or fluorescein)
used for acute attack of angle closure glaucoma
Mannitol IV injection