Pharmacology
Glucocorticoids
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Get access- Applied topically, subconjunctivally, systemically to suppress inflammation
- Mechanisms of action
- Reduce the number of PMLs, lymphocytes, macrophages
- Affect vascular permeability
- Inhibit phospholipase A2 and the eicosanoids
- Inhibit histamine release
- Inhibit cytokine gene transcription in lymphocytes and APCs
- Side effects
- Cataract: correlates with the daily dosage, especially if >15mg daily prednisolone
- Posterior subcapsular
- Reactivation of viral keratitis
- Increased risk of bacterial infection
- Steroid induced IOP rise: via GAG and water accumulation in the TM reducing outflow
- 30% of normal people are steroid responsive with varying severity of response
- Patients with POAG have a greater overall response
- Risk factors for steroid response
- POAG
- Pigmentary glaucoma
- FHx of glaucoma
- FHx of steroid response
- High myopes
- Diabetics
- Usually presents within 2-4 weeks of starting steroids but can occur years later
- Loteprednol causes less IOP elevation
- Less likely with oral steroids compared to topical agents
See Part 2 package for comprehensive exploration of glaucoma including steroid-induced glaucoma
- Corneal penetration
- Higher concentrations increase penetration
- Prednisolone is hydrophilic and therefore penetrates poorly
- Acetate forms of dexamethasone and prednisolone penetrate better