Pharmacology

Question 1

Drops: Advantages and Disadvantages

Answer 1

Advantages:
     Targeted delivery
     Generally well-tolerated
     Reduced systemic side effects
     Decreased Antibiotic resistance
Disadvantages:
     Local irritation, toxic or allergic reactions
     Some medications not well-absorbed
     Duration in tear film less than 5 minutes

Question 2

Ointments: Advantages and Disadvantages

Answer 2

Advantages:
     Increase the contact time
     Soothing to ocular surface
Disadvantages:
     Blurring of vision
     Limited availability of medications in ointment form

Question 3

Purposes of ocular medications

Answer 3

Diagnosis
Treatment of eye diseases
prevention of eye diseases
Prescription often required
Exceptions: (available over the counter)
Artificial tears (lubricating over the counter)
Ocular decongestants (decease eye redness)

Question 4

Ocular medications are used to treat

Answer 4

Glaucoma
Infections
Other

Question 5

Possible side effects of ocular medications

Answer 5

Redness
Stinging
Blurred vision
Sensitivity to light
Constriction or dilation of pupil
Allergic reactions

Question 6

How to properly use ocular medications

Answer 6

Wash your hands
Confirm that the patient is not allergic to the medicine (or preservative for medics, if applicable) that will be applied (review chart, question patient)
Check the expiration date
Shake the container
Tilt the patient’s head back and instruct them to look up
Gently pull the lower lid away from the eye, forming a pouch by the inferior fornix
Place one drop (1/4 to 1/2 inch of ointment) in the pouch; (Note: Do not touch the eye or eyelid with the container or dropper to avoid contamination)
For drops, instruct the patient to close his/her eye and press his/her finger against the inner corner of their eyelid and the side of their nose, in order to prevent the draining away; inform the patient of any possible side effects, e.g., burning, redness
For ointment, instruct the patient to close their eye; inform them to expect their vision to be blurry for a few minutes
Repeat with the other eye if required
Replace the cap or dropper n the bottle or tube and tighten

Question 7

Topical Anesthetics and Diagnostic Agents

Answer 7

Among the most commonly used topical agents in an ophthalmology office
Used for ocular examination and minor procedures
Rapid onset of anesthesia generally last for 20-30 minutes

Question 8

Topical (applied directly to a part of the body) anesthetics

Answer 8

May be used once or twice for ocular examination and treatment
Repeated use can damage the epithelium, impair healing, and even result in corneal melting
Patients should never be given topical anesthetic for use at home

Question 9

Dyes for examination of the ocular surface

Answer 9

Fluorescein

Lissamine green and rose bengal

Question 10

Fluorescein

Answer 10

Applied in the form of a solution or from sterile strips
Renders tear film visible to assess. quality and stability
Aids in applanation tonometry
Stains defects n the corneal and conjunctival epithelium

Question 11

Lissamine green and rose bengal

Answer 11

Available as solutions or dye impregnated strips
Similar to fluorescein but stain devitalized cells
Useful in evaluating dry eye conditions
Lissamine green is less irritating than rose bengal

Question 12

Commonly used anesthetic

Answer 12

Generic Name: Cocaine (1%-4%)
Generic name: Proparacaine (arcane, oculi-caine, ophthetic, paracaine) (0.5%)
Generic name: Tetracaine (Pontocaine) (0.5%, 1.0%, 2.0%)

Question 13

Mydriatics and Cycloplegics

Answer 13

Very commonly used
Affect the autonomic innervation of the eyes to produce mydriasis (pupillary dilation) and cycloplegia (paralysis of accommodation)
Facilitate examination and testing
Therapeutic use for relief of photophobia associated with intraocular inflammation
Can induce angle closure, especially in some hyperopes
Check chamber depth before dilating a patient for the first time
Considerable variation in onset and duration based on underlying ocular conditions, age, eye color and other factors
Provide temporary sunglasses to patients
Advise caution with driving or operating machinery.

Question 14

Common Mydriatics and cycloplegics

Answer 14

Phenylephrine (AK-dilate, Mydfrin, Neo-synephrine) (2.5%, 10%) (Onset: 30-60 min) (Duration: 3-5 hours)
Tropicamide (Mydriacyl, tropicacyl) (0.5%, 1.0%) (Onset: 20-40 min) (Duration: 4-6 hours)
Cyclopentolate (AK-Pentolate, cyclogyl, calate) (0.5%, 1.0%, 2.0%) (Onset: 30-60 min)(Duration: 6-24 hours)
Homatropine (Isopto Homatropine) (2%, 5%) (Onset: 30-60 min) (Duration: 3 days)
Scopolamine (Isopto Hyoscine) (0.25%) (Onset:30-60 min) (Duration: 4-7 days)
Atropine (Atropine-care, Isopto Atropine) (1.0%) (Onset: 45-120 min) (Duration: 7-14 days)

Question 15

Ocular Anti-inflammatory medications

Answer 15

Inflammation is associated with infection, trauma, surgery, allergic/toxic reactions, and auto-immune diseases
Pain, redness and photophobia common indications of acute inflammation
Chronic Inflammation can lead to increased intraocular pressure, cataracts, and scarring
Steroids and non-steroidal anti-inflammatory medications (NSAIDs)
Combined with injectable/systmic meds for severe inflammation

Question 16

Non steroidal Anti inflammatories (NSAIDs)

Answer 16

Non-specific; block specific inflammatory mediators
Reduce redness, photophobia, pain
Side effects; local irritation to the ocular surface/impaired healing
Rarely associated with keratitis and corneal melting

Question 17

Steroids

Answer 17

More potent but potentially serious side effects
Increase intraocular pressure, accelerated cataract formation and potentiation of some infections
Anti-microbails often used concurrently
New “designer” steroids less likely to cause side effects

Question 18

Endophthalmitis

Answer 18

Rare but serious interocular infection
Associated with recent surgery, injury or immunocompromised individuals
Specimens for culture often obtained in the operating room
Concurrent injection of intraocular antimicrobials
Often requires systemic therapy

Question 19

Corneal ulcers require aggressive therapy

Answer 19

Specimens from corneal scraping for cultures/slides for staining
Topical therapy-broad spectrum/specially formulated fortified antibiotics
Compounding pharmacies
Around the clock treatment

Question 20

Treatment or ocular infections due to bacteria, viruses, fungi or protozoans

Answer 20

More often used for prophylaxis (pre-operative, minor injuries)
Available as solutions, ointment, and as injectable forms
Various mechanisms of action and spectrums of activity
Cultures or slides for identification of the organism may guide therapy
Broad spectrum antibiotics (or combinations) typically institute prior to culture results
Treatment adjusted based on response/laboratory results

Question 21

Miotics

Answer 21

Once the mainstay of topical glaucoma therapy, but are now used less frequently
Require frequent dosing and cause pupillary constrictions

Question 22

Combination products

Answer 22

Simplify dosing regiment

Actions and side effects related to individual components

Question 23

Anti-Allergy and Dry eye medications

Answer 23

Environmental allergies effect approximately 15% of the general population
Systemic medications often ineffective in treating ocular symptoms

Question 24

Mild allergies

Answer 24

Artificial tears and cool compresses may suffice

Over the counter medications are available for ocular allergies, as well as prescription medications

Question 25

Moderate to severe allergies

Answer 25

Prescription medications Medications block inflammatory mediators involved in the allergic response Steroids reserved for severe allergies unresponsive to other therapies Newer steroids with improved safety now used for allergic eye disease.

Question 26

Dry eyes

Answer 26

``` Artificial tears Preserved or non-preserved Puntual plugs Anti-inflammatory medications Immune modulating medications ```

Question 27

Mainstay of glaucoma therapy

Answer 27

Various mechanisms of action

Question 28

Alpha Agonists

Answer 28

Short term use to prevent increased pressure after laser treatment Long-term use for the treatment of open-angle glaucoma Side effects; fatigue and other CNS effects; often less bothersome with adaptation

Question 29

Beta Blockers

Answer 29

Selective and non-selective formulations Systemic side effects: slowing of the heart rate, hypotension and exacerbation of asthma Selective beta blockers may decrease side effects

Question 30

Carbonic Anhydrase Inhibitors (CAI)

Answer 30

Decrease aqueous production Systemic or topical Side effects: GI upset, tingling, and parenthesis and altered taste and smell Metabolic disturbances and, rarely, bone marrow suppression Topical use decrease side effects Avoid in patients with sulfonamide allergies.

Question 31

Prostagladins

Answer 31

Effective and convenient Local hyperemia, itching, and stinging Darkening of iris and increased peri-ocular pigmentation Enhanced growth of the lashes Avoid in patients with a history of iritis or herpetic eye infections.