What are the recommended treatments for a patient with a red eye, pressure behind the affected eye, and a headache?

Red Eye with Pressure and Headache: Urgent Evaluation Required

This presentation demands immediate ophthalmologic evaluation to rule out acute angle-closure glaucoma, a sight-threatening emergency that can cause permanent blindness within hours if untreated. 1

Immediate Assessment Priority

The combination of red eye, pressure sensation behind the eye, and headache is highly suspicious for acute angle-closure glaucoma (AACG), which constitutes an ophthalmologic emergency requiring urgent intervention. 1, 2 Patients with AACG typically present with sudden onset of severe eye pain, headache, nausea, vomiting, decreased vision, corneal edema, and very high intraocular pressure. 1

Critical Red Flags Requiring Same-Day Ophthalmology Referral:

• Severe pain not relieved by over-the-counter analgesics 3
• Vision loss or blurred vision 3, 2
• Mid-dilated, poorly reactive, or oval-shaped pupil 1
• Corneal haziness or edema 1
• Nausea or vomiting accompanying eye symptoms 1, 4
• Unilateral presentation 5, 4

Differential Diagnosis Framework

While AACG is the most concerning diagnosis, other conditions must be considered:

High-Risk Conditions (Require Urgent Referral):

• Acute angle-closure glaucoma: Presents with severe pain, headache, pressure sensation, mid-dilated pupil, corneal edema, and markedly elevated IOP 1, 2
• Acute iritis/anterior uveitis: Causes photophobia, pain, and requires ophthalmology consultation 3, 2
• Infectious keratitis: Presents with severe pain, photophobia, and requires specialist management 3, 2
• Scleritis: Deep, boring pain that may radiate to the head, requires ophthalmology evaluation 3, 2

Moderate-Risk Conditions:

• Intermittent angle-closure: Can cause pain and headache without obvious redness, may present with blurred vision and halos around lights 1, 6
• Optic neuritis: Headache with visual deficit in younger patients 6
• Giant cell arteritis: In patients over 50, consider temporal arteritis with associated headache, jaw claudication, and vision changes 7

Lower-Risk Conditions:

• Conjunctivitis: Most common cause of red eye, but typically presents with discharge rather than severe pressure or headache 1, 3
• Blepharitis: Eyelid inflammation, less likely to cause significant pressure sensation 1

Immediate Management Steps

In Primary Care Setting:

1. Check visual acuity immediately - Any vision loss mandates urgent referral 3, 2

2. Assess pupil size and reactivity - Mid-dilated, poorly reactive pupil suggests AACG 1

3. Evaluate pain severity - Severe, unrelenting pain with headache is concerning for AACG 1, 2

4. Look for corneal clarity - Corneal edema or haziness indicates serious pathology 1, 3

5. Determine laterality - Unilateral red eye with severe pain and vomiting is highly suspicious for acute glaucoma 4

Critical Action Points:

Do NOT prescribe topical corticosteroids or anesthetics in primary care - These can worsen certain conditions (HSV keratitis, adenoviral infections) and mask serious pathology 1, 4

Refer immediately to ophthalmology if:

• Severe pain is present 3, 2
• Vision is impaired 3
• Pupil is distorted or poorly reactive 1, 3
• Corneal involvement is suspected 3, 4
• Patient has nausea/vomiting with eye symptoms 1

Special Considerations

For Patients Over 50 Years:

Evaluate for giant cell arteritis by checking for temporal artery tenderness, jaw claudication, weight loss, or proximal myalgia. 7 Order ESR and CRP urgently, as these are elevated in GCA with 76% sensitivity and 86% specificity. 7 If GCA is suspected, initiate prednisone 1-2 mg/kg/day immediately to prevent vision loss in the fellow eye. 7

Medication History:

Ask specifically about recent use of:

• Anticholinergic medications (can precipitate angle closure) 1
• Topiramate or sulfonamides (can cause ciliary body edema and angle narrowing) 1
• Adrenergic agents or phenothiazines 1

Risk Factors for Angle-Closure:

• Hyperopia (farsightedness) 1
• Family history of acute angle closure 1
• Asian ethnicity 1
• Older age with thickening lens 1

Common Pitfalls to Avoid

Never assume this is "just conjunctivitis" when pressure sensation and headache are prominent features - conjunctivitis rarely causes significant pressure or severe headache. 1, 3

Do not delay referral for "observation" - AACG can cause permanent vision loss within hours, and 18% of untreated eyes become blind. 1

Avoid empiric antibiotic treatment without proper evaluation - This delays appropriate diagnosis and can mask serious conditions. 1

Do not check intraocular pressure with contact tonometry if acute conjunctivitis is suspected - This can spread infection; defer IOP measurement unless absolutely necessary. 1