SSRI Selection to Minimize Glaucoma Risk
Based on current evidence, citalopram, escitalopram, or sertraline should be preferred over fluoxetine and paroxetine when prescribing SSRIs to patients at risk for glaucoma, as these agents have lower rates of adverse effects in vulnerable populations and may pose less risk. 1
Evidence for SSRI-Associated Glaucoma Risk
The relationship between SSRIs and glaucoma is established but varies by individual agent and patient characteristics:
All SSRIs as a class increase glaucoma risk, particularly with longer duration of treatment (>365 days) and higher doses (≥1 defined daily dose), with an adjusted odds ratio of 1.36 for extended use 2
The mechanism involves mydriasis (pupil dilation) that can precipitate angle-closure in susceptible patients, though SSRIs pose less risk than tricyclic antidepressants 3
Fluoxetine specifically has been shown to increase intraocular pressure in clinical studies, even after a single dose, though effects were initially asymptomatic 4
The risk is highest in patients under 65 years of age (adjusted OR = 1.37), without diabetes, hypertension, or hypercholesterolemia 2
Recommended SSRI Selection Strategy
First-Line Choices for Patients at Glaucoma Risk:
Citalopram, escitalopram, or sertraline are preferred in older adults due to lower rates of adverse effects compared to fluoxetine and paroxetine 1
Sertraline has particular advantages including a low potential for drug interactions at the cytochrome P450 level and well-established tolerability in elderly patients who are at higher baseline glaucoma risk 5
Agents to Avoid:
Fluoxetine should be avoided in patients with glaucoma risk factors, as it is the most activating SSRI and has documented effects on increasing intraocular pressure 1, 4
Paroxetine should be avoided in older adults due to higher rates of adverse effects 1
Critical Monitoring Requirements
All patients receiving SSRIs require ophthalmological evaluation before starting treatment and during therapy if they have glaucomatous risk factors, especially elderly patients 4:
- Baseline assessment of iridocorneal angle configuration
- Measurement of intraocular pressure
- Evaluation for narrow angles or other anatomical predispositions
Monitor specifically for:
- Visual disturbances (often dismissed but may indicate IOP changes) 4, 6
- Symptoms of angle-closure: eye pain, halos around lights, blurred vision, headache 3
- Mydriasis (pupil dilation) which is often transient but can promote angle closure 3
Important Clinical Caveats
The incidence of SSRI-related IOP modifications is likely underestimated because most cases present as pauci-symptomatic or asymptomatic intermittent angle-closure rather than acute attacks 4
Duration and dose matter significantly: Risk increases substantially with treatment exceeding one year and at higher therapeutic doses 2
Angle-closure glaucoma represents the most important SSRI-related ocular adverse event, though it remains relatively uncommon 6
Patients with pre-existing narrow angles appear to experience glaucomatous attacks when exposed to medications with anticholinergic or mydriatic properties, making baseline screening essential 3