How does prednisone (corticosteroid) affect patients with glaucoma?

How Prednisone Affects Glaucoma

Prednisone and other corticosteroids significantly increase intraocular pressure (IOP) in patients with glaucoma, potentially causing irreversible optic nerve damage, and should be used with extreme caution or avoided when possible in this population. 1, 2

Mechanism of IOP Elevation

Corticosteroids, including prednisone, cause morphological and functional changes in the trabecular meshwork system—the same pathogenic mechanism seen in primary open-angle glaucoma (POAG). 3 The FDA label explicitly warns that corticosteroid use may produce glaucoma with possible damage to the optic nerves. 1

Risk Stratification for Steroid-Induced IOP Elevation

High-Risk Patients (46-92% will develop elevated IOP):

• Patients with existing POAG 3
• Family history of POAG 2
• Age over 40 years 3
• Diabetes mellitus 3
• High myopia 3

General Population Risk:

• 18-36% of individuals without glaucoma are "steroid responders" who will develop elevated IOP 3

Route-Specific Considerations

The risk varies significantly by administration route:

Topical ophthalmic corticosteroids pose the highest risk for IOP elevation. 4 The American Academy of Ophthalmology guidelines specifically note that aggressive topical corticosteroid treatment can cause undetected IOP elevation. 4

Systemic corticosteroids (including oral prednisone) also elevate IOP, though the effect may be less pronounced than topical administration. 5 One study demonstrated that dexamethasone and betamethasone (both topical and systemic) are more potent in producing glaucoma than other preparations. 5

Nasal corticosteroid sprays can significantly increase IOP in glaucoma patients. A study showed mean IOP increased from 15.4 mm Hg pre-steroid to 18.0 mm Hg during nasal steroid use, with significant reduction to 14.5 mm Hg after discontinuation. 6

Intravitreal corticosteroids carry particularly high risk. Studies of intravitreal triamcinolone and dexamethasone implants showed IOP elevation rates of 16-18% at one year. 4 The American Academy of Ophthalmology specifically warns that intraocular pressure elevations are particularly common with intravitreal corticosteroids and corticosteroid implants. 7

Clinical Monitoring Algorithm

For patients with glaucoma requiring corticosteroids:

1. Baseline assessment: Document current IOP, optic nerve status, and visual field before initiating steroids 4

2. Monitoring frequency:

   • If steroid therapy continues beyond 6 weeks, IOP must be monitored regularly 1
   • For topical ophthalmic steroids: Check IOP at weeks 1-2 and 1 month postoperatively 8
   • For systemic steroids: Follow IOP after initiation and throughout treatment 2

3. Duration considerations: Keep treatment duration as short as possible (ideally within 1 month) with gradual tapering 8

Reversibility and Permanent Damage

Critical distinction: The IOP elevation caused by corticosteroids is reversible upon discontinuation, but the optic nerve damage produced by elevated IOP is irreversible. 5 Studies show that when steroid duration is short, the condition is reversible without permanent damage; prolonged use leads to irreversible damage. 5

Discontinuation of nasal steroids resulted in IOP reduction within 35 days on average, with sustained reduction at 191 days. 6 Many patients were able to avoid or delay additional glaucoma therapy after steroid discontinuation. 6

Management When Corticosteroids Are Necessary

If corticosteroids cannot be avoided in glaucoma patients:

• Use the lowest effective dose and shortest duration possible 1
• Consider less potent preparations (medrysone or prednisolone over dexamethasone or betamethasone) 5
• Initiate or intensify IOP-lowering medications concurrently 2
• For ophthalmic use, consider preservative-free formulations 8
• Educate patients about the risk and importance of monitoring 2, 3

Contraindications: The FDA label states corticosteroids should not be used in active ocular herpes simplex because of possible corneal perforation. 1 The American Academy of Ophthalmology guidelines note that corticosteroid use is an exclusion criterion when diagnosing POAG, as it represents secondary glaucoma. 4

Special Clinical Scenarios

Post-surgical settings: While postoperative corticosteroids after trabeculectomy significantly improved surgical success (94% vs 43% stabilization rate at 5 years), this must be balanced against steroid-induced IOP elevation risk. 9 Close monitoring is essential in this context.

Cataract surgery: Standard protocol includes short-term topical steroids (2-4 weeks) with IOP monitoring at weeks 1-2 and 1 month. 8 For patients with pre-existing glaucoma, this monitoring becomes even more critical.