Ophthalmic Conditions Study Notes

Community Pharmacy Practice II: Ophthalmic Conditions

Learning Outcomes

At the end of this topic, students should be able to:

  1. Discuss the different clinical features of red eye.

  2. Identify red eye that can be managed by a pharmacist and those with red flags that need referral to a physician.

  3. Discuss the management of red eye that can be managed by a pharmacist.

  4. Discuss the different types of eyelid disorders and their management.

  5. Provide the counselling points for eye drops and eye ointment.

Eye Anatomy

  • The eye is a STERILE organ.

  • Important anatomical structures include:
      - Superior rectus muscle: Responsible for moving the eye upwards.
      - Optic nerve: Transmits visual information from the retina to the brain.
      - Limbal area: The border between the cornea and sclera.
      - Conjunctiva and episclera: Membranes covering the front of the eye and inner eyelids.
      - Eyelid: Protects the eye and distributes tears.
      - Lacrimal puncta: Drains tears from the eye.
      - Pupil and Iris: Regulates the amount of light entering the eye.
      - Sclera: The white outer coating of the eyeball, providing protection and structure.

Red Eye

  • Definition: A common presenting complaint of both severe and non-severe ophthalmic conditions. One of the most frequently encountered ocular complaints in primary care is conjunctivitis.

  • Conjunctivitis: Inflammation of the conjunctiva which is the transparent surface covering the white of the eye. It can be due to infectious etiology or non-infectious (e.g., allergies).

Bacterial Conjunctivitis

  • Causative Organisms: Common bacteria include:
      - Staphylococcus aureus
      - Streptococcus pneumoniae
      - Haemophilus influenza
      - Moraxella catarrhalis

  • Symptoms/History:
      - Purulent discharge from the eye.
      - Lid crusting.
      - Symptoms may start with one eye but often affect both eyes within 2 days.

  • Management: Usually self-limiting (~7 days). Treatment includes:
      - Antibiotic eye drops/ointment to speed recovery.
      - Short-term use of steroids is advised; prolonged steroid use can exacerbate issues.
      - Common antibiotics include chloramphenicol 0.5%, gentamicin 0.3%, fusidic acid 1%, and tobramycin 0.3% + dexamethasone 0.1% eye drop.

Chloramphenicol 0.5% vs. 5%

  • The two formulations differ in their strengths.

  • The 0.5% preparation is preservative-free, while the 5% preparation contains preservatives such as phenylmercuric nitrate.

  • Dosage and Administration: For topical application:
      - Instill 1-2 drops into affected eye(s) four to six times a day for the first two days, after which dosing can be reduced.
      - Continue treatment for 48 hours after the eye appears normal to ensure complete cure.

Viral Conjunctivitis

  • Common Causes: Most commonly caused by adenoviruses in adults and herpes simplex virus (HSV) in neonates.

  • Symptoms/History:
      - Bilateral onset of redness and gritty sensation.
      - Watery discharge.
      - Often accompanied by pharyngitis and cough, especially in adenovirus infection.

  • Management: Usually self-limiting (~5-7 days). Treatment involves:
      - No role for topical antibiotics in viral infections.
      - Use of artificial tears to reduce discomfort.
      - Avoid steroid eye drops as they may prolong the adenovirus infection.

Allergic Conjunctivitis

  • Common Cause: Rhinoconjunctivitis (hay fever).

  • Symptoms/History:
      - Bilateral presentation with watery discharge.
      - Itching.
      - Often associated with rhinitis or history of eczema/asthma.

  • Management:
      1. Mast Cell Stabilizers (e.g., sodium cromoglycate): Prevent the release of inflammatory mediators; useful for prevention but do not relieve existing symptoms. Loading period about 3 to 7 days; suitable for children >4 years old.
        - Dosage: 1 drop QID.
      2. Sympathomimetics & Antihistamines:
        - Vasoconstrictor: Naphazoline 0.025% to reduce redness but does not resolve the underlying cause; recommended for short-term use only.
        - Antihistamines: Pheniramine 0.3%, Olopatadine 0.1% or 0.2% for controlling itch and allergy.
        - Dosages for adults include:
          - Naphcon A: 1 drop QID.
          - Patanol 0.1%: 1 drop BD for >3 years old.
          - Pataday 0.2%: 1 drop OD for >3 years old.

Comparison of Conjunctivitis

Type

Symptoms

Characteristics of Eye

Discharge

Eyes Affected

Associated Symptoms

Bacterial

Superficial, gritty pain

Superficial, gritty pain

Purulent

Unilateral often, but both affected within 48 hours

None usually

Viral

Superficial, gritty pain

Superficial, gritty pain

Watery

Bilateral

Pharyngitis/cough

Allergic

Superficial, itchy

Superficial, itchy

Watery

Bilateral

Rhinitis

Other Causes of a Red Eye

  1. Keratitis: Inflammation of the cornea, often caused by infections or irritants (e.g., contact lens). Symptoms often include:
       - Unilateral acute pain.
       - Photophobia.
       - Decreased vision.
       - Can have either watery or purulent discharge.

  2. Scleritis: Involves inflammation of the sclera, associated with autoimmune diseases (e.g., rheumatoid arthritis). Symptoms often include:
       - Severe, radiating pain to the face, jaw, and head.
       - Mild photophobia.
       - Blurred vision, with 50% bilateral cases.

  3. Episcleritis: Inflammation between sclera and conjunctiva, usually painless with redness and swelling but no discharge. Usually self-limiting, resolving in 2 to 3 weeks.

  4. Uveitis: Inflammation of the iris or anterior ciliary body. Symptoms include:
       - Unilateral pain, photophobia, decreased vision.
       - Often linked to systemic autoimmune diseases.

  5. Subconjunctival Hemorrhage: Ruptured blood vessel under conjunctiva, typically resolves within 2 weeks. History of trauma should be evaluated to exclude ocular injury. Monitor patient's blood pressure.

  6. Glaucoma: Two main types:
       - Open-angled (chronic): Painless, gradual loss of peripheral vision then central vision.
       - Closed-angled (acute): Rapid onset with severe pain, nausea, vomiting, blurred vision, and requires immediate referral.

  7. Dry Eyes (Keratoconjunctivitis Sicca): Caused by decreased tear production or excessive evaporation, with symptoms including dryness, redness, foreign body sensation, and photophobia.

Management of Dry Eyes

  • Common over-the-counter products include:
      - Lubricant-based drops (e.g., Hypromellose, HPMC, CMC, PEG-400).
      - CMC base eye drops are more viscous and effective than HPMC.
      - Moisture-locking drops contain sodium hyaluronic acid 0.1% (e.g., Hialid).
      - Prescription products: Diquafosol sodium 3%, Cyclosporin 0.05%.

Examples of Eye Drops/Ointments

  • Hialid: 0.1% ophthalmic solution for dry eye, compatible with contact lenses.

  • Chloramphenicol Eye Ointment: 10 mg/g, provides lubrication and hydration for dry eye sensations.

Eye Drops vs. Eye Ointments

  • Eye drops offer quick relief; however, they may not provide prolonged hydration.

  • Eye ointments are preferred for longer-lasting hydration but require less frequent application and can blur vision temporarily.

Patient Interview & History Taking

Key points to inquire:

  • For whom? Identify the patient experiencing red eye.

  • Duration: How long has the condition existed? Any previous treatments?

  • Discharge: Any flaky/sticky eyes upon waking?

  • Pain description: Any pain or discomfort?

  • Photophobia: Severe cases may indicate more serious pathology.

  • Location of redness: Different locations may help identify the underlying cause.
      - Redness towards the corner usually indicates conjunctivitis, while localized redness near the pupil suggests possible serious issues.

  • Associated Symptoms: Check for itchiness, rhinorrhea, headaches, etc.

Red Flags for Referral

Trigger Points Indicative of Urgent Referral:

  • Clouding of the cornea

  • Associated vomiting

  • Redness caused by a foreign body

  • Irregularly shaped pupil or abnormal pupil reactions to light

  • Severe photophobia

  • True eye pain

  • Distortion of vision

  • Redness localized around the pupil

Summary

  • Recognize and differentiate the forms of conjunctivitis (bacterial, viral, allergic) and their symptoms and management approaches.

  • Understand other causes of red eye and appropriate referrals.

Eyelid Disorders

Blepharitis

  • Inflammation of the eyelid margin, may be anterior or posterior:
      - Anterior blepharitis: Caused by staphylococcal and seborrheic conditions affecting eyelash bases.
      - Posterior blepharitis: Results from meibomian gland dysfunction.

  • Symptoms include swelling, redness, crusting, burning sensation, and foreign body sensation.

Management of Blepharitis

  • Improve lid hygiene with warm compresses for 10 minutes and follow with cleaning using diluted baby shampoo or eyelid wipes.

  • Use preservative-free artificial tears to treat dry eye symptoms.

  • Topical antibiotics (e.g., gentamicin 0.3% eye drop, fusidic acid 1% eye drop) may be required.

Hordeolum (Stye)

  • Common sequel of infectious blepharitis, often due to S. aureus infections.

  • External hordeolum occurs from infection at the base of eyelashes, while a more painful internal hordeolum involves deeper glands.
      - Management: Warm compression several times daily; may require antibiotic drops/ointment.

Chalazion

  • Blocked meibomian gland leading to a painless lump; usually self-limiting.

  • No specific treatment required but surgery may be needed if vision is obstructed.

Eye Contact Dermatitis

  • Caused by exposure to irritants like cosmetics or soaps.

  • Symptoms include erythema, swelling, and itchiness.

  • Management includes avoidance of triggering agents, eyewash, cold compress, and antihistamines (topical or oral).

Counselling for Eye Drops

Steps for administration:

  1. Wash hands and sit in front of a mirror.

  2. Unscrew the cap of the bottle.

  3. Tilt head back and look upward.

  4. Pull down the lower eyelid gently.

  5. Hold dropper above eye(s) and squeeze one drop into lower eyelid.

  6. Avoid touching the tip of the dropper.

  7. Close eyes for a short while, do not blink.

  8. Wipe any excess with tissue.

  9. Securely close the cover and store accordingly.

  10. Wait for 5 minutes before applying another drop if required.

Counselling for Eye Ointment

Steps for administration:

  1. Wash hands and sit in front of a mirror.

  2. Unscrew the cap of the ointment tube.

  3. Tilt head back and pull down lower eyelid.

  4. Squeeze 1 cm of ointment inside the lower eyelid without touching surfaces.

  5. Close the eye for about 2 minutes for absorption; blurriness may occur temporarily.

  6. Wipe off any excess with tissue.

  7. Store appropriately after replacing cap.

Food for Eye Health

Certain foods and supplements beneficial for eye health include:

  • Lutein

  • Zeaxanthin

  • ß-carotene (Vitamin A)

  • Astaxanthin

  • Omega-3 fatty acids

Conclusion

  • Understanding the various aspects of ophthalmic conditions helps in efficient management, patient counselling, and determining when to refer patients to specialists.