What are the symptoms of acute angle closure glaucoma?

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Acute Angle Closure Glaucoma: Clinical Presentation

Acute angle closure glaucoma (AACG) presents with sudden onset of severe eye pain, blurred vision with halos around lights, eye redness, a mid-dilated poorly reactive pupil, corneal edema, and markedly elevated intraocular pressure, often accompanied by nausea, vomiting, and severe headache. 1, 2

Cardinal Ocular Symptoms

  • Severe eye pain that is sudden in onset and may be accompanied by headache 1, 2, 3
  • Blurred vision resulting from pressure-induced corneal edema creating a characteristic "steamy" or hazy corneal appearance 1, 4
  • Halos around lights (multicolored haloes) due to corneal edema 1, 2
  • Eye redness from conjunctival and episcleral vascular congestion secondary to markedly elevated IOP 1, 4

Systemic Symptoms

  • Nausea and vomiting are systemic manifestations of the acute IOP spike 1, 2, 4
  • Severe headache that may be the predominant presenting complaint 2, 3, 5

Key Physical Examination Findings

  • Mid-dilated, poorly reactive or fixed pupil in the affected eye (may appear oval or asymmetric) 1, 4, 6
  • Corneal edema with microcystic and stromal edema 1
  • Conjunctival hyperemia (vascular congestion) 1
  • Shallow anterior chamber on slit-lamp examination 1, 4
  • Markedly elevated intraocular pressure (typically >40 mmHg) 2, 4

Intermittent Angle Closure Warning Symptoms

Patients may experience prodromal episodes before acute crisis that should never be dismissed as benign. 2, 6 These warning symptoms include:

  • Transient blurred vision that resolves spontaneously 1, 2
  • Halos around lights during episodes 1, 2
  • Eye pain or headache following stress or dilated eye examination 1
  • Symptoms triggered by dim lighting or pupil dilation 1

The presence of bilateral transient episodes with halos, opaque vision, and eye pain is pathognomonic for intermittent angle closure, which carries a 50% risk of acute crisis within 5 years if left untreated. 2, 6

Critical Clinical Pitfalls

Acute angle closure can rarely present without pain, mimicking amaurosis fugax or other painless causes of vision loss, making the diagnosis more challenging. 7 The American Academy of Ophthalmology emphasizes that transient symptoms should never be dismissed as benign, as these represent warning episodes before potentially blinding acute attacks. 2, 6

The fellow eye is at extremely high risk for developing acute angle closure, with untreated fellow phakic eyes having increased risk of acute attacks. 1 Eighteen percent of eyes become blind (10% from glaucoma) within 4-10 years following an untreated AACG. 1, 4

Medication-Induced Triggers

Patients should be specifically questioned about medications that may precipitate angle closure, including: 1

  • Anticholinergic agents (antihistamines, motion-sickness medications, phenothiazines) 1, 8
  • Adrenergic agents (decongestants, ephedrine, salbutamol inhalers) 1, 8
  • Sulfa-based drugs (topiramate, acetazolamide, hydrochlorothiazide, cotrimoxazole) causing ciliary body edema 1, 8
  • Antidepressants (tricyclic and tetracyclic) 1, 8

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Acute Angle-Closure Glaucoma Diagnosis and Treatment

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Acute angle closure glaucoma.

British journal of hospital medicine (London, England : 2005), 2019

Guideline

Acute Right Eye Pain with Pressure Sensation: Critical Diagnoses and Management

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Differential Diagnosis for Eye Pain

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Drug-induced acute angle closure glaucoma.

Current opinion in ophthalmology, 2007

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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