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Chapter 40
AGENTS USED IN THE TREATMENT OF CONDITIONS OF THE EYES
The eyes draw images from the light reacting off the retina, and these images are transmitted by way of
the optic nerve for interpretation by the brain. The lens is divided by the iris into an anterior and a
posterior chamber that are filled with water aqueous humor that bathes the eye constantly to prevent
it from drying, which would cause its fragility.
Mydriatic Agents
Mydriatic drugs are agents that dilate the pupil
Sympathomimetic Mydriatics
◦ Produce pupillary dilation, increase the outflow of aqueous humor, cause vasoconstriction, relax the
ciliary muscle, and decrease the formation of aqueous humor
◦ Moderate strength: used in management of narrow-angled glaucoma
◦ Weaker solution: used as opthlamic decongestants for symptomatic relief of minor eye irritants
Anticholinergic Mydriatics
◦ Blocks the response of the sphincter muscle of the iris and the muscle of the ciliary body to cholinergic
stimulation
◦ Produces dilation of the pupil and may interfere with the ability of the eye to focus properly
◦ Should NOT be used with patients with glaucoma
Ophthalmic Anti-Infectives
Antibacterial Agents
Antifungal Agents
Antiviral Agents
Ophthalmic Antibacterial Agents
Used in the eye to treat superficial infections caused by strains of
microorganisms susceptible to the antibiotic in the product
Classified into:
◦ Macrolides
◦ Aminoglycosides
◦ Fluoroquinolones
◦ sulfonamids
Ophthalmic Antibacterial Agents
Azithromycin (AzaSite)
◦ Macrolide antibacterial ophthalmic solution used for treatment of bacterial
conjunctivitis
◦ Broad-spectrum
◦ Prolong use can result in resistant organisms
Ophthalmic Antibacterial Agents
Fluoroquinolone agents
◦ floxacin HCl (Besivance)
◦ Used to treat bacterial conjunctivitis caused by susceptible bacteria
◦ Approved for use in clients as young as 1 year of age
◦ Most common adverse effect: conjunctival redness
◦ Prolonged use may present a risk of superinfection
◦ Ciprofloxacin (Ciloxan)
◦ Available as an ophthalmic solution and ointment forms
◦ Effective against both gram-positive and gram-negative ocular pathogens
◦ Used in the treatment of corneal ulcers and conjunctivitis caused by susceptible organisms
◦ Adverse effects: local burning, margin crusting, foreign body sensation, itching, conjunctival hyperemia, and bad taste after ocular
instillation
◦ gatiflocaxin (Zymaxid)
◦ Used for the treatment of bacterial conjunctivitis
◦ Effective agin certain aerobic gram-positive microorganisms and aerobic gram-negative bacteria
◦ Common adverse effects: headache, unpleasant taste, decreased visual acuity, eye pain, eye discharge, eyelid edema, dry eye,
headache, and red eye
Ophthalmic Antibacterial Agents
Aminoglycoside
◦ Gentamicin ophthalmic ointment/solution
◦ Used in the treatment of conjunctivitis, keratitis, keratoconjunctivitis, corneal ulcers, blepharitis,
blepharoconjunctivis, acute meibomianitis, and dacryocystitis caused susceptible strains of
microorganisms
◦ Most common adverse effects: ocular burning and irritation, conjunctivitis, conjunctival hyperemia,
allergic reactions, thrombocytopenia purpura, and hallucinations
Antifungal Agents
Natamycin (Natacyn)
◦ Effective in treatment of blepharitis, fungal conjunctivitis, and keratitis caused
by certain fungal organisms
◦ If no improvement after 7-10 days of therapy, it is concluded that the infection
is not cause by an organism susceptible to natamycin
Antiviral Agents
Idoxuridine (Herplex)
◦ Indicated for the treatment of keratitis caused by the herpes simplex virus
◦ Important to monitor the progress of the diseases carefully to determine if the client is responding
Vidarabine (Vira-A)
◦ Active against herpes simplex type 1 and 2, varicella zoster, and several other viruses
◦ Client should be monitored for the development of burning, irritation, or any other adverse changes in the eye
while using this medication
Trifluridine (Viroptic)
◦ An agent that also mayyy be used to treat viral infections of the eye
◦ Effective in the treatment of hepes simplex types 1 and 2 infections
◦ Ocular toxicity may result if used for longer than 21 days
Antisepticspg 1304
Solutions of boric acid, zinc sulfate, and some of the surface-wetting agents are
used primarily as ocular irrigants
Solutions of silver nitrate or mild silver protein are used to precipitate and
remove accumulated mucus from the eye
Antiseptic action may be attributed to precipitation of bacterial protein by
liberated silver ions
Ocular irrigationpg1309
Most often used to flush chemical irritant's, blood splatters or small particles
from the eye.
Sterile 0.9% Sodium Chloride is commonly used
Navstel (balanced salt ophthalmic solution with hypromellose, dextrose and
glutathione disulfide), for use during ocular surgical procedures involving
perfusion of the eye
Anytime ocular irrigation is performed great care must be taken to prevent
excessive pressure that could damage ocular structures
Local Anestheticspg1309
Used in procedures where topical ophthalmic anesthetic is required (i.e. Tonometry, gonioscopy,
removal of foreign objects or stitches from the cornea or any other surgical procedure of short
duration
1 drop into the eye is generally administered shortly before the measurement or procedure is to
be initiated, the blinking reflex is temporarily eliminated while the eye is anesthetized state
Most commonly used local anesthetic in the US is proparacaine HCI, however an approved new
formulation of lidocaine HCl as an ophthalmic anesthetic, Akten
Take care with use of these agents, prolonged exposure to the eye can produce corneal
opacification and ulceration accompanied with vision loss
Corticosteroids
Used in the eye to exert anti-inflammatory action
Uses:
-Relieves pain and discomfort to the eye due to: trauma, allergic
infection.
Side effects:
-prolonged use may result in glaucoma
-damage to structure of the eye
-cataract formation
-increased susceptibility to infection
reaction, and ocular
Contraindications and examples
Contraindicated in fungal and viral infections because steroids may facilitate
their spread.
Examples:
-Difluprednate
-Loteprednol
-Rimexolone
-Ozurdex
Nonsteroidal Anti-Inflammatory Agents
Cyclosporine (Topical immunomodulator/ anti-inflammatory)
Uses:
-Chronic dry eye due to ocular inflammation associated with keratoconjunctivitis sicca.
Adverse effects:
-Ocular burning, pruritus, stinging
-Conjunctival hyperemia
-Foreign body sensation, eye pain
No known drug interactions
Diclofenac Sodium (NSAID)
Uses:
- postoperative inflammation following cataract surgery.
-postoperative pain and photophobia associated with corneal refractive surgery.
Adverse effects:
-Keratitis, transient burning, stinging on instillation
-Nausea and vomiting
-Increased IOP, ocular allergy
No known drug interactions
Flurbiprofen Sodium (NSAID)
Uses:
-Prevention of intraoperative miosis
Adverse effect:
-Ocular irritation
-Transient burning and stinging
No known drug interactions
Ketorolac Tromethamine (NSAID)
Uses:
-Seasonal allergic conjunctivitis, burning
-Postoperative pain, stinging following corneal refractive surgery,
follow incisional refractive surgery.
Adverse effects:
-Transient burning and stinging with instillation
-Ocular irritation, allergic reaction
-Superficial ocular infections and superficial keratitis
No know drug interactions
photosensitivity
Ophthalmic Antihistamines
Used to treat conjunctivitis related to allergies
Bepotastine (Bepreve)
◦ Allergic conjunctivitis
◦ Indicated in adults and children 2 years and older
◦ Ophthalmic solution
◦ Not used for contact lens irritation
Adverse Effects
◦ Mild taste after instillation, eye irritation, headache, & nasopharyngitis
Ophthalmic Antihistamines (cont.)
Epinastine HCl (Elestat)
◦ Dual action antihistamine
◦ Prophylaxis for itching
◦ Mast cell stabilizer
◦ Administer one drop per eye twice a
day
Adverse Effects
◦ Burning sensations, pruritus, redness,
etc (pg. 1310)
Ophthalmic Antihistamines (cont.)
Levocabastine HCl (Livostin)
◦ Relieves S/SX of seasonal allergic conjunctivitis
◦ Adults and children 12 years and older
◦ One drop per eye four times per day
Adverse Effects
◦ Burning or stinging when administered, dry eyes & mouth, headache,
& sleepiness
Other Agents Used For The Eyes
Dapiprazole HCL (Rev-Eyes)
◦ Alpha-Adrenergic blocking agent to constrict the pupil
◦ Not used more than once a week
Artificial Tears (Isopto Tears, Lacril, Tearisol, Tears Naturale)
◦ Provide tear like lubrication for dry & irritated eyes
◦ Can be used to lubricated contact lenses & artificial eyes
Ocular Hypertension
Any increase in intraocular pressure (IOP)
◦ Described as being greater than 21 mm Hg in one or both eyes
(Normal is between 13-20 mm Hg)
◦ No apparent abnormalities with the optic nerve
◦ No signs of glaucoma
◦ Not considered a disease
Glaucoma
Characterized by an increase IOP that results in damage to the ocular nerve and
blindness
May be caused by:
◦ An acquired structural defect within the eye (primary glaucoma)
◦ The consequence of another ocular disease or trauma
(secondary glaucoma)
◦ The result of a genetic defect (congenital glaucoma)
◦ If left untreated, may lead to optic nerve degeneration, loss of visual field, and eventual
blindness
Glaucoma
Aqueous humor production is produced by an enzyme called carbonic anhydrase, as well as
other enzyme systems
Normally, production and output of aqueous humor remain within defined limits, usually less
than 20 mm
In glaucoma, increased intraocular pressure is cause by a blockage of the outflow mechanism
If the pressure is unrelieved, the optic nerve eventually is injured and destroyed
This degeneration is evidenced symptomatically:
◦ 1. loss of visual field
◦ 2. loss of central visual acuity
◦ 3. total blindness
Glaucoma
Open-angle glaucoma
◦ The most common form
◦ No change in the chamber angle of the eye
◦ Due to local degenerative changes, aqueous outflow is impeded
◦ Narrow-angled glaucoma
◦ Iris occludes the anterior chamber angle structures
◦ Normal outflow is prevented
◦ Dilation of the pupil may precipitate an acute glaucoma attack by causing the bunched-up iris to block the outflow of aqueous
humor
◦ Generally requires a surgical procedure, iridectomy
Agents that Decrease the Formation of Aqueous
Humor
Carbonic Anhydrase Inhibitor
◦
◦
◦
◦
◦
Inhibit the action of the enzyme carbonic anhydrase
Reduces the amount of humor produced decreasing IOP
Treatment for open-angle glaucoma and preoperative management of acute narrow-angle glaucoma
All of the drugs in this category are diuretics
Do NOT use if sensitive to sulfonamide
Osmotic Diuretics
◦ Administered orally or parenteral
◦ Reduce the production of aqueous humor in the eye and thereby reduce IOP
◦ Used to treat acute episodes of narrow-angle glaucoma or in preparation for surgery of glaucoma and other
eye disorders
◦ NOT for chronic use
◦ Use with CAUTION in clients with renal impairment
Agents that Decrease the Formation of
Aqueous Humor
Beta-Adrenergic Blocking Agents
◦
◦
◦
◦
◦
◦
Applied topically
Lower IOP by a mechanism believed to result in reduced formation of aqueous humor
Have little effect on pupil size or visual acuity, therefore do not cause blurred vision or night blindness
Use with CAUTIOUN in patients with bronchia asthma and congestive heart failure
May cause ocular irritation and slightly reduce the rest HR of some clients
Drugs: Timolol maleate (Temoptic), timolol hemihydrate (Betimol), betaxolol HCl (Betoptic), levobunolol
HCl (Betagan), carteolol (Ocupress), and metipranolol HCl (Optipranolol)
Glaucoma Nursing Practice
Assessment includes determination of visual acuity and IOP, inquiry about visual changes and
headaches, and specific questioning about the use of medications in the eye
Carbonic anhydrase inhibitors should not be taken near bed time. Have the client report tingling in
the fingers and toes, urticaria, and evidence of weight loss or changes in BP
many ophthalmic solutions/drops may cause a temporary dimming or blurring of vision. Provide for
client safety
Never use an ophthalmic solution that is cloudy or has changed its ways
Many ophthalmic solutions/drops may cause a temporary dimming or blurring of vision. Provide for
patient safety.
Clients with asthma who are taken pilocarpine must be monitored for pulmonary edema and
asthmatic attacks
Always be certain the proper medication is being used in the correct eye
Agents that INCREASE the outflow of
Aqueous Humor
Direct-Acting Miotics, agents mimic the action of the neurotransmitter acetylcholine and act to
constrict the pupil and contract the ciliary muscle (ex. Pilocarpine), acetylcholine may be used
Miotics that inhibit Cholinesterase activity, agents prevent enzymatic destruction of
acetylcholine within the eye inhibiting the enzyme, cholinesterase, they are more toxic and
longer acting than the direct-acting miotics, generally for use in open-angle glaucoma who don’t
respond to other forms of drug therapy, cholinesterase inhibitors may cause local or systemic
adverse effects
Agents that DECREASE formation and
INCREASE outflow of Aqueous Humorpg 1325-1326
Progstaglandin Analogs, (ex. Bimatoprost, lantanoprost and travoprost) reduce intraocular
pressure by increasing aqueous humor outflow, used for open-angled glaucoma and ocular
hypertension and considered 2nd line treatment, because tends to change color of the iris
Sympathomimetic Agents, (ex. Epinephrine) stimulate adrenergic receptors within the eye,
initially may result in a reduction of aqueous humor production, prolonged therapy with these
drugs may result in an increase in the outflow of aqueous humor, caution must be used in older
adults and in clients with hypertension, DM, hyperthyroidism, or HD
Dipiverfrin HCI (propine) is an agent that penetrates the cornea about 17times faster
than epinephrine and once absorbed is converted to epinephrine by enzyme hydrolysis within
the human eye; believed to be less irritating than other forms of epinephrine therapy
Nursing Interventions
Direct-actin Miotics, monitor for flushing, sweating, GI distress, diarrhea and headache
Miotics inhibit cholinesterase, monitor for toxicity, atropine sulfate or pralidoxime chloride (2PAM) may be used as an antidote
Prostaglandins analogs, advise clients that wear contact lens to remove their contacts prior to
instillation of this solution
Sympathomimetic agents, use only in open-angled glaucoma because of the mydriatic effect
may precipitate an acute glaucoma attack to client who have narrow-angle glaucoma prior to an
iridectomy
Questions
What antidote can be used in toxicity with cholinesterase-inhibiting drugs?
What is Ocular Hypertension?
Normal range?
What is Ocular Hypertension?
Normal range?
General term to describe any increase in intraocular pressure or pressure inside the eye that is
greater than 21 mm Hg in one or both eyes
Normal range is between 13-20 mm Hg