Week 6 - Inflammatory eye diseases Flashcards
Anti-inflammatory drugs used in eyecare
• Sympathomimetics*
• NSAIDs
-Systemic
- Topical Ocular
• Corticosteroids
What are Sympathomimetics? How do they work?
• used in differential diagnosis
• Active ingredient: adrenergic alpha agonists
• Promote contraction of smooth muscle which lines conjunctival blood vessel walls
• Vasoconstrictive action on conjunctival blood vessels
What type of sympathomimetic is available to us?
• used in differential diagnosis Episcleritis vs Scleritis
• Phenylephrine hydrochloride 2.5% and 10%
• Mydriatic and vasoconstrictive properties on conjunctiva and episcleral. Does not vasoconstrict deeper , larger scleral BVS
Entry Level Optometrists, Orthoptists, IP/Shared Care Practitioners
Sympathomimetics contraindications:
• Hypersensitivity
Systemic adrenergic effects mean that these drugs should not be used in patients with:
• cardiac disease, hypertension, aneurysms, tachycardia
• Asthma
• Thyrotoxicosis
• long-standing insulin-dependent diabetes
•Patients on MAOIs, tricyclic antidepressants and antihypertensive agents
• Patients with closed-angle glaucoma or narrow angles
Sympathomimetics systemic cautions and ocular side effects:
• Risk of systemic effects; avoid 10% in infants and elderly
• Ocular side effects:
- Photophobia
- Corneal clouding (10% concentration and damaged epithelium)
- mydriasis (action on pupil dilator muscle)
- Check anterior chamber angle
Inflammatory cascade:
• Phospholipids from the cell’s plasma membrane is where prostaglandins synthesise
• Phospholipase A2 enzyme becomes active when inflammatory response
• Arachidonic acid is transformed via
- Cyclo-oxygenase enzyme into Prostaglandins
- or Lipoxygenase enzyme into Leukotrienes
NSAIDS:
• Non-Steroidal Anti-Inflammatory Drugs.
• Inhibit action of the cyclo-oxygenase (COX) enzyme.
- However doesnt inhibit leukotrines via Lipoxygenase enzyme, therefore there will still be some inflammatory mediators
Cyclo-Oxygenase (COX) types:
- COX-1: Normal processes in uninflamed tissues
• Stomach acid levels
• Gastric protection - COX-2: Synthesis of prostaglandins in inflamed tissues
• Many NSAIDs are non-selective
• Inhibition of COX-1 has the potential to cause gastro-intestinal side effects (e.g. nausea, stomach ulcers, peptic bleeding)
Systemic NSAIDs: indications
• Wide range of indications
• Three major properties:
- Anti-inflammatory (control inflammatory response)
- Analgesic (relief from pain)
- Anti-pyretic (control fever)
• Some are available as GSL and P medications
• Eye care practitioners may recommend that patients use systemic NSAIDs to manage mild to moderate pain (e.g. corneal abrasion)
Types of Systemic NSAIDs and cautions:
• Ibuprofen +
• Aspirin +
• Diclofenac Sodium PoM*
• Naproxen PoM*
Available to entry level optometrists/orthoptists +
Only available to IP practitioners*
Cautions:
• Not be used by patients with an allergy to aspirin
• Avoid in patients with blood clotting disorders
• Avoid in patients with gastro-intestinal problems
Topic ocular NSAIDs: used for
• Greater therapeutic effect on ocular region
• Reduced risk of systemic side effects
• Minimal ocular side effects
• Some patients may develop a hypersensitivity
• Used to control and provide relief from the symptoms of ocular inflammation:
- Corneal abrasion
- Seasonal allergic conjunctivitis
- Episcleritis
- Ocular procedures/surgery
Topic ocular NSAID’s Availability and types:
• Only available as PoMs
• Typical dosing regimen: 2-4 times per day
• Diclofenac Sodium
• Flurbiprofen
• Ketorolac
• Nepafenac
IP/Shared Care Practitioners ✔️
Corticosteroids:
• Steroids are hormones which naturally occur within the body
• Steroids regulate innate responses (e.g. inflammation, allergy, immune system)
• Corticosteroids: both naturally occurring steroids and the synthetic medications which are designed to mimic their action
• Mode of action: inhibit release of phospholipase A2 enzyme
Corticosteroids: Indications
• Used to control ocular inflammation
• Reduces sensation of pain
• Reduces risk of ocular tissue damage due to prolonged inflammatory reactions and scarring
- Scleritis
- Anterior uveitis
- Severe allergic conjunctivitis
- Ocular surgery
• All PoMs
IP / Shared Care Practitioners ✔️
Corticosteroid dosing:
• Initially intensive (e.g. 1 drop every 2 hours for first 48 hours)
• Reduce to normal therapeutic dose (e.g. QDS)
• Abrupt cessation may cause rebound effect
• ‘Taper’ dose gradually over a number of weeks
• Balance of tapering versus risks associated with prolonged use
Corticosteroids drugs available
• Fluoromethalone
• Betamethasone
• Loteprednol
• Prednisolone
• Dexamethasone
• Can be found in combination with antibiotic
Entry Level Optometrists X
Orthoptists X
IP / Shared Care Practitioners ✔️