Is citalopram safe for a patient with glaucoma, and what precautions are needed for narrow‑angle versus open‑angle disease?

Citalopram and Glaucoma

Citalopram can be used in patients with open-angle glaucoma without special precautions, but requires careful risk assessment and ophthalmologic screening before use in patients with narrow angles or those at risk for angle-closure glaucoma. 1

Key Distinction: Open-Angle vs. Angle-Closure Risk

The FDA label explicitly states that "pre-existing glaucoma is almost always open-angle glaucoma because angle closure glaucoma, when diagnosed, can be treated definitively with iridectomy. Open-angle glaucoma is not a risk factor for angle closure glaucoma." 1 This is the critical distinction that guides management.

For Patients with Open-Angle Glaucoma

• Citalopram is safe to use without additional monitoring beyond standard glaucoma care
• Open-angle glaucoma patients are not at increased risk for angle-closure episodes from citalopram
• Recent meta-analysis data actually suggests SSRIs may be associated with modest IOP reduction (Hedges' g = -0.332) and reduced open-angle glaucoma risk (OR = 0.832) 2

For Patients at Risk of Angle-Closure Glaucoma

The FDA warns that citalopram can cause mild pupillary dilation, which "in susceptible individuals, can lead to an episode of angle closure glaucoma." 1 The mechanism involves pupillary dilation triggering angle closure in anatomically narrow angles.

Who is susceptible:

• Patients with anatomically narrow iridocorneal angles who lack a patent iridectomy 1
• Hypermetropic (farsighted) individuals
• Older adults
• Asian populations (higher prevalence of narrow angles) 3
• Anyone without prior iridectomy who has narrow angles on gonioscopy

Clinical Algorithm

Before prescribing citalopram:

1. Ask about prior glaucoma diagnosis:

   • If diagnosed open-angle glaucoma → Proceed with citalopram (no additional precautions needed)
   • If diagnosed angle-closure glaucoma with prior iridectomy → Proceed with citalopram (iridectomy provides definitive treatment)
   • If diagnosed angle-closure glaucoma without iridectomy → Ophthalmology referral first

2. Screen for anatomic risk factors:

   • Hypermetropia (near-sightedness)
   • Age >50 years
   • Asian ethnicity
   • Family history of angle-closure glaucoma
   • Shallow anterior chamber (if known)

3. For high-risk patients without known glaucoma:

   • The FDA recommends: "Patients may wish to be examined to determine whether they are susceptible to angle closure, and have a prophylactic procedure (e.g., iridectomy), if they are susceptible." 1
   • Consider ophthalmology referral for gonioscopy before starting citalopram
   • Prophylactic laser peripheral iridotomy eliminates the risk 3, 4

Patient Counseling

Warn all patients starting citalopram to seek immediate care if they develop:

• Sudden eye pain
• Blurred vision or halos around lights
• Eye redness
• Headache with nausea

These symptoms suggest acute angle-closure glaucoma, which is an ophthalmologic emergency requiring immediate treatment to prevent permanent vision loss 3.

Important Caveats

The actual incidence of citalopram-induced angle closure is rare but potentially blinding when it occurs. Case reports document both typical pupillary-block angle closure 5 and atypical mechanisms involving uveal effusions (similar to escitalopram, citalopram's active enantiomer) 6. The uveal effusion mechanism involves ciliary body edema with anterior rotation of the iris-lens diaphragm and does not respond to iridotomy—requiring drug discontinuation, cycloplegics, and corticosteroids instead 6.

Do not confuse this with other antidepressants: Topiramate (an anticonvulsant sometimes used in psychiatry) has a much stronger association with angle closure (OR = 3.93) through a completely different mechanism and represents a higher-risk medication 2, 4.