Ophthalmic Disorders

Required Reading

• DiPiro Chapter e15: Minor Ophthalmic Disorders (for dry eyes)

• DiPiro Chapter 119: Glaucoma

Objectives

• Define common ophthalmic disorders requiring pharmacologic management.

• Define first-line pharmacologic treatments for common ophthalmic disorders. Note some second-line included.

• Describe the Mechanism of Action (MOA) for indicated drug therapy for ophthalmic disorders.

• List adverse effects, drug interactions, contraindications and monitoring for selected pharmacologic agents used for ophthalmic disorders.

• Utilize critical thinking skills to develop an appropriate individualized infection-related therapeutic treatment plan.

• Demonstrate appropriate techniques for administering common ophthalmic drug products.

Selected Ophthalmic Disorders

• Dry Eye Syndrome

• Conjunctivitis

  • Bacterial

  • Viral

  • Allergic

• Blepharitis

• Glaucoma

Dry Eye Syndrome

Causes of Dry Eye Syndrome (DES)

• Decreased production of tears

• Increased drainage through tear ducts

• Poor tear quality

Etiology of DES

• Symptoms include burning and redness (friction)

• Large Lacrimal Gland: Essential for tear production

• Dry Eye Triggers: Environmental factors impacting tear stability such as:

  • Tear Chemistry

  • Tear film imbalance

  • Lasting damage to the eye surface

  • Swollen eyes (eye surface inflammation)

  • An unhealthy eye environment

• Meibomian Glands: Secrete oils that help form tears (oil, water, mucus)

Tear Types in DES

• Lubricating (Basal): Continuous production; has natural antibiotic properties.

• Reflex (Bolus): Released in response to sudden irritation, emotion, injury, etc.

• Note: DES can increase reflex tear production which exacerbates DES, leading to
  watery eyes as a sign of DES.

Risk Factors for DES

• Advanced age

• Contact lens wear: Increases tear evaporation

• Hormonal changes: Especially in women (pregnancy, oral contraceptives, menopause)

• Diseases: Such as Bell's palsy, Sjogren's syndrome, rheumatoid arthritis (RA), lid defects, ocular rosacea

• Environmental factors: Smoke, dust, high altitude, hot/cold air, sunlight, wind, air pollution

• Medications: Include β-blockers, diuretics, narcotics, alcohol (ETOH), SSRIs, atypical antipsychotics, oxybutynin, clonidine, antihistamines

Management Overview for DES

• Non-pharmacologic therapy:

  • Avoid irritants

  • Use a humidifier

  • Don't stare at screens for long periods

• OTC Therapy:

  • Artificial tears:

  • Chosen based on comfort required

  • Higher viscosity = more retention and greater symptom relief

  • Initial dosing: Start with daily or BID (twice a day) then increase to TID (three times a day) or QID (four times a day)

1st Line Treatment for DES

• Artificial Tears (Lubricant Drops):

  • Preservative-free options: for frequent administration (≥4x daily).

  • Examples include Sodium perborate and Purite, which are disappearing preservatives.

  • Example Products:

  • Genteal, Refresh Liquigel, Refresh Tears, Genteal Gel (with preservatives)

  • Bion Tears, Celluvisc, Refresh Optive, HypoTears PF (preservative-free but more expensive, unit-dose)

Alternate 1st Line Treatment for DES

• Artificial Tears - Ointments and Gels:

  • Enhance tear film integrity due to increased retention in the eye.

  • Must be preservative-free.

  • Main ingredients: White petrolatum, mineral oil, lanolin.

  • Adverse Effects: Blurry vision

  • Recommended use at bedtime.

Preservatives in Ophthalmic Products

• Many ophthalmic products include preservatives such as:

  • Benzalkonium chloride (BAK) and benzethonium chloride: Toxic to tear film and epithelium.

  • Methylparaben and propylparaben: Unstable at high pH; may induce allergic reactions.

2nd Line Treatment for DES

• Cyclosporine 0.05% ophthalmic emulsion (Restasis):

  • MOA: Inhibits activation of T-cells, increases tear production in patients presumed to have decreased tear production due to inflammation.

  • Dosage: 1 drop each eye, BID.

  • Adverse Effects: Burning in up to 17% of users; may take up to 3 months to work; may induce remission.

• Lifitegrast (Xiidra):

  • MOA: Lymphocyte Function-Associated Antigen 1 (LFA-1) Antagonist; reduces inflammation by inhibiting binding of cell mediators.

  • Dosage: 1 drop each eye, BID.

  • Adverse Effects: Change in taste (up to 25%), local irritation, decreased visual acuity.

Optional Treatment for DES

• Perfluorohexyloctane (Miebo):

  • MOA: Forms a layer on the tear film surface reducing tear evaporation.

  • Indicated for dry eye associated with tear evaporation due to meibomian gland dysfunction where less meibum is formed.

  • More effective than saline but lacks trials against other drugs for dry eye.

  • Dosage: 1 drop each eye QID; contacts should be removed and all use stopped for 30 minutes following administration.

• Varenicline (Tyrvaya):

  • Administration: Intranasal solution; MOA: Cholinergic agonist activating the trigeminal parasympathetic pathway to increase basal tear production.

  • Dosage: 1 spray in each nostril twice daily, requiring 7 pumps before first use if not used for over 5 days; each spray provides 0.03 mg varenicline.

  • Adverse Effects: Sneezing (82%), cough (16%), throat irritation (13%).

Conjunctivitis

Types of Conjunctivitis

Conjunctivitis Overview

Acute Bacterial Conjunctivitis (ABC)

Definitions:

• ABC: Erythema of the bulbar conjunctiva with purulent discharge and bilateral matting of eyelids, no itching.

• Hyperacute ABC: Neisseria gonorrhoeae infection resulting in copious discharge, eye pain, decreased vision and rapid progression.

Etiology of ABC

• Gram Positive Organisms:

  • Streptococcus pneumoniae

  • Staphylococcus aureus

• Gram Negative Organisms:

  • Haemophilus influenzae

  • Neisseria meningitidis

  • Neisseria gonorrhoeae

Treatment of ABC

1st Line Treatment

• Polymyxin B/trimethoprim (Polytrim):

  • Dosage: 1 drop every 3 hours for 7-10 days.

  • Adverse Effects: Redness, burning, stinging.

• Ciprofloxacin (Ciloxan):

  • Dosage:

  • Days 1-2: 1-2 drops every 2 hours while awake.

  • Days 3-7: 1-2 drops every 4 hours.

  • Ointment: 1 cm ribbon up to 3 times daily for 2 days; then BID for 5 days.

  • Adverse Effects: Blurry vision, redness, burning.

• Polymyxin B with bacitracin:

  • Dosage: Ointment: 1 cm ribbon every 3-4 hours for 7-10 days.

• Erythromycin 0.5%:

  • Dosage: Ointment: 1 cm ribbon up to 6 times daily.

Hyperacute Treatment

• Culture and sensitivity testing.

• Ceftriaxone: 1g IM, Topical antibiotics.

• Referral to ophthalmologist.

Viral Conjunctivitis

Definition (Pink Eye):

• Erythema of the bulbar conjunctiva, with watery discharge and mild to no itch.

Management of Viral Conjunctivitis:

• Highly contagious; stay home until no discharge; do not share eyewear or linens.

• Practice frequent hand washing.

• Use cool compresses QID.

• Use artificial tears (preferably preservative-free).

• Steroids may reduce scarring in severe cases but prolong viral shedding (+ 2 weeks).

Key Facts on Viral Conjunctivitis:

• Commonly caused by adenovirus.

• Initially starts in one eye then spreads rapidly to the other.

• Contagious for approximately 14 days.

• Self-limiting; typically resolves in 2-3 weeks.

Allergic Conjunctivitis

• Mechanism: IgE-mediated hypersensitivity reaction to pollen, animal dander, or dust.

• Symptoms: Red sclera with edema, itching, tearing, nasal congestion; typically bilateral.

Non-pharmacologic Measures for Allergic Conjunctivitis:

• Symptomatic relief with cold compresses.

• Avoid allergen contact.

• Maintain proper hand hygiene.

• Discontinue medication if induced by medications (common with overuse of topical decongestants/vasoconstrictors).

Select Ocular Products for Allergic Conjunctivitis

Blepharitis

Overview of Blepharitis

• Healthy Eyelid: Normal structure and function.

• Blepharitis: Eyelid swollen and reddened, with scaly scabs often due to a bacterial infection.

Etiology of Blepharitis

• Commonly associated organisms include:

  • S. epidermidis

  • S. aureus

  • Seborrheic dermatitis

  • Can be a combination of these factors.

Signs and Symptoms of Blepharitis

• Red, scaly, thickened eyelids

• Loss of eyelashes

• Itching, burning; often chronic in nature.

Management of Blepharitis

• Lid Scrubs: Remove oil, debris, and desquamated skin. Wash lid margins with baby shampoo and warm compress every 24 hours.

• Follow up with:

  • Erythromycin or bacitracin ointment is applied daily at bedtime to the lid margin.

  • Artificial tears consider if there is a concomitant DES presentation.

Glaucoma

Types of Glaucoma

• Primary Open Angle Glaucoma (POAG)

• Primary Angle Closure Glaucoma (PACG)

• Drug-Induced “Glaucoma” (increased intraocular pressure)

Description of Glaucoma Types

• POAG:

  • Characterized by slow blockage of the drainage canals, leading to increased intraocular pressure.

  • Has a wide and open angle between the iris and cornea.

  • Develops slowly, lifelong condition, and symptoms are often unnoticed.

  • Accounts for 90% of all cases.

• PACG:

  • Resulting from blockage of the drainage canals, leads to a sudden rise in intraocular pressure.

  • The angle between the iris and cornea is closed or narrow.

  • Develops rapidly with noticeable symptoms, requiring immediate medical attention.

Anatomy Related to Glaucoma

Structures Involved in POAG vs PACG

• POAG:

  • Drainage through trabecular meshwork.

  • Commonly entails chronic management.

• PACG:

  • Sudden intraocular pressure elevation must be managed urgently.

Drug-Induced Increases in Intraocular Pressure (IOP)

• For Open Angle Glaucoma:

  • Corticosteroids: HIGH RISK (both ophthalmic and systemic).

  • Ophthalmic anticholinergics, Fenoldopam, Succinylcholine.

• For Closed Angle Glaucoma:

  • Anticholinergics (Topical and Systemic), Antihistamines, Ipratropium, SSRIs/TCAs/Venlafaxine, Topical sympathomimetics.

Treatment Goals

• For POAG: Aim for IOP to be 25% lower than pre-treatment IOP; focus on medical management.

• For PACG: Requires rapid reduction in IOP; definitive treatment by iridectomy allows for proper aqueous humor flow.

Therapeutic Overview

First Line Agents for Glaucoma Management

• Prostaglandin Analogs (e.g., Latanoprost)

• Beta-Blockers (e.g., Timolol)

Second Line Agents

• Adrenergic Agonists

• Carbonic Anhydrase Inhibitors

• Cholinergic Agonists

• Surgical Interventions

Prostaglandin Analogs – Mechanism and Side Effects

• MOA: Increases aqueous humor outflow; reduction in IOP of 25-35%.

• Adverse Effects:

  • Altered iris pigmentation, increased lash pigmentation, eye pruritus.

  • Better tolerated and more effective than timolol.

• Cost: Generic Latanoprost $10-$25, Brand Xalatan $270.

Specific Prostaglandin Analog Examples

• Latanoprost (Xalatan): 1 drop every night.

• Bimatoprost (Lumigan) and Travoprost (Travatan Z): Both with similar properties, with preservative-free options in single-use containers.

Beta-Blockers – Mechanism and Side Effects

• MOA: Decreases aqueous humor production, similar effectiveness among agents; choose based on individual response and cost.

• Examples:

  • Timolol (Timoptic): 1 drop BID or daily if pressure is controlled.

  • Cost: $25-$35 for 10ml.

Beta-Blocker Overview

Clinical Activity Case Study

• A 65-year-old male inquiring about his new medication:

  • Medication: Latanoprost (Xalatan) 1 drop in both eyes at bedtime.

  • Questions: Is the dose and frequency appropriate? What is an important side effect to counsel on for this medication?

Administration Technique for Eye Drops

• Steps:

  • Wash hands thoroughly.

  • Open the bottle carefully to avoid touching the dropper tip.

  • Tilt head back.

  • Gently pull down eye lid to create a pocket.

  • Look up and squeeze one drop into the pocket of the lower lid.

  • Avoid blinking, or touching the dropper tip to the eye or face.

  • Close the eye and keep it closed for three minutes.

  • If more than one type of eye drop is to be used, wait 5 minutes before administering the next.

  • Recap the dropper and discard or replace after 30 days.

Administration Technique for Ointments and Gels

• Steps:

  • Wash hands thoroughly.

  • Open the tube while avoiding contact with the application tip.

  • Tilt the head back.

  • Pull down the lower lid to form a pocket.

  • Apply one ribbon into the pocket of the lower lid.

  • Close the eye and keep closed for 1-2 minutes.

  • Wipe excess with tissue and clean the tip of the tube with another tissue.

  • Recap the tube and discard or replace after 30 days.

Patient Education

• Emphasize the importance of Nasolacrimal Occlusion (NLO) for enhancing the effectiveness of drops.

Conclusion

• Note: The material presents an extensive overview of ophthalmic disorders, highlighting key management strategies, treatment options, and practical administration techniques required for effective pharmaceutical care in visual health treatments.