Angle closure risk from proprietary medicines

Illicit drugs: Effects on eye

There is a myriad of changes that can be produced in the eye by toxic drugs ranging from mild/no symptoms to severe loss of vision from endophthalmitis. The routes of administration include oral ingestion, smoking, nasal inhalation, intravenous injection, topical application or application to other mucosal surfaces. It is important to recognize certain clinical signs and symptoms in the eye produced by these toxins. This article describes in brief some of the ocular effects of commonly abused drugs. For identification of a particular poisoning, in addition to the clinical presentation, pulse, blood pressure, respiration and body temperature, pupillary size, pupillary reaction to light, ocular convergence and nystagmus can be useful indicators of the type of drug the patient is exposed to. Unmasking these features help the clinician in an early and accurate diagnosis of the offending drug as well as timely management.

Has the EAGLE landed for the use of clear lens extraction in angle-closure glaucoma? And how should primary angle-closure suspects be treated?

Angle-closure glaucoma is an aggressive condition that causes millions to become blind worldwide. This review explores the use of prophylactic laser peripheral iridotomy (PI) in patients classified as primary angle-closure suspects (PACS), and additionally, the use of clear lens exchange as a primary treatment option in established angle-closure disease with or without glaucoma. As PI has a strong prophylactic effect in fellow eyes of patients who have had an acute attack, its use has been widely adopted in those patients classified as PACS, but with limited evidence to support this. A large randomised trial conducted in China has demonstrated that although PI reduces the risk of incident angle-closure disease, the incidence of disease that would threaten vision was much lower than anticipated. This suggests that the benefit of prophylactic PI is very limited. Health services data shows an association between rising cataract surgical rates and of decreasing rates of acute angle-closure. Age-related growth of the lens is a major component of angle-closure disease. Several studies have shown that clear lens extraction (CLE) effectively lowers IOP in angle-closure. The use of CLE as a primary treatment option has been tested against LPI in the EAGLE study, a large RCT that enroled people with angle-closure and an IOP > 30 mmHg, and those with angle-closure glaucoma. The trial showed CLE to be superior to PI both for IOP control and patient reported quality of life. On these grounds, CLE should be considered for first-line treatment of more advanced angle-closure disease.

Single Dose of Pseudoephedrine Induces Simultaneous Bilateral Acute Angle Closure Crisis

Simultaneous bilateral acute angle closure crisis (AACC) is a sight-threatening ocular emergency. Many “cold and flu” preparations contain compounds with sympathomimetic or anticholinergic qualities that confer a risk of inducing AACC. We present a review of cold and flu preparation-induced AACC, and present a case of simultaneous bilateral AACC triggered by a single oral dose of pseudoephedrine. The challenges facing the clinician in recognizing simultaneous bilateral AACC in the context of an upper respiratory tract infection are addressed. An awareness of this uncommon clinical entity, its pertinent clinical features, risk factors, and the drug classes that may precipitate an attack is critical for the timely diagnosis and management of this ocular emergency. Notably, clinicians must be aware that even a single dose of an implicated medication may trigger an attack of AACC.

Drug-induced Acute Angle-closure Glaucoma: A Review

Aim

Our goal is to review current literature regarding drug-induced acute angle-closure glaucoma (AACG) and provide ophthalmologists and general practitioners with a thorough understanding of inciting medications and treatment pitfalls to be avoided.

Background

Drug-induced AACG is an ophthalmological emergency that ophthalmologists and general practitioners should be familiar with, given its potentially blinding consequences. Common anatomical risk factors for AACG include a shallow anterior chamber depth, short axial length, plateau iris configuration, thick lens, anteriorly positioned lens, and rarely, intraocular tumor. Demographic risk factors include female sex, Asian ethnicity, family history, and advanced age. In patients with predisposing factors, acute angle closure can be triggered by various classes of medications including adrenergic agonists, anticholinergics, cholinergics, sulfonamides, supplements, and serotonergic medications. Physicians prescribing such inciting medications should be aware of their potentially sight-threatening adverse effects and to inform patients of the warning symptoms. Patients typically present with elevated intraocular pressure (IOP), headache, nausea, blurry vision, and halos around lights.

Review results

There are two main mechanisms of drug-induced AACG, both with different treatment strategies. The first mechanism of drug-induced AACG is pupillary block and iridocorneal angle closure secondary to thickening of iris base with mydriasis. The second mechanism of drug-induced AACG is anterior displacement of the lens-iris diaphragm due to mass effect (e.g., blood, misdirected aqueous humor, and tumors), uveal effusion, or weakened zonules.

Conclusion

This paper reviews drug-induced AACG, high-risk anatomical features, underlying mechanisms, inciting medications, and options for treatment and prevention.

Clinical significance

With proper understanding of the underlying mechanism of drug-induced AACG, physicians can respond promptly to save their patients' vision by employing the correct treatment strategy.

How to cite this article

Yang MC, Lin KY. Drug-induced Acute Angle-closure Glaucoma: A Review. J Curr Glaucoma Pract 2019;13(3):104-109.

Bilateral acute myopia and angle closure glaucoma induced by Ma-huang (Ephedra): A case report

RATIONALE

Cases of bilateral acute angle closure have been reported after use of various drugs.

PATIENT CONCERNS

A 52-year-old woman visited the emergency room and complained of acute bilateral ocular pain and decreased vision accompanied by headache, nausea, and vomiting. One day before, she had started a herbal medicine containing Ma-huang for weight loss. On examinations, myopic shift, edematous cornea, increased intraocular pressure, shallow anterior chamber, and thickened choroid on both eyes were observed.

DIAGNOSES

Angle closure glaucoma induced by drug (Ma-huang).

INTERVENTIONS

To promptly quit the offending drug and apply ocular hypotensives and cycloplegics.

OUTCOMES

Her symptoms and signs were relieved after antiglaucoma medications and no significant recurrence has been occurred.

LESSONS

Physicians prescribing weight loss medications containing Ma-huang must be aware of the potentially sight-threatening adverse effect of bilateral acute angle closure.

Pharmacological and environmental factors in primary angle-closure glaucoma

INTRODUCTION OR BACKGROUND

A large number of drug classes have now been reported to provoke angle closure in high-risk individuals. The mechanism of action can be generalized into three main categories: sympathomimetic, parasympatholytic and idiosyndratic reactions.

SOURCES OF DATA

This review of the ophthalmic literature provides a clinical summary of primary angle-closure glaucoma (PACG) and its management.

AREAS OF AGREEMENT

External stimuli (pharmacological and environmental) may induce acute, and more often, asymptomatic angle closure, which carries a significant risk of glaucoma.

GROWING POINTS

Whenever in doubt, patients at risk of PACG who are starting on drug therapy known to provoke angle closure or aggravate the condition should be referred for detailed gonioscopic examination of the anterior chamber by an ophthalmologist. AREAS FOR DEVELOPING RESEARCH: The use of new imaging methods such as anterior segment optical coherence tomography to assess the presence or risk of angle closure is gaining popularity, and may offer a more rapid method of identifying people who are at risk of sight loss from angle-closure glaucoma precipitated by non-ophthalmological medication.