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Apraclonidine (EENT) (Monograph)

Brand name: Iopidine
Drug class: alpha-Adrenergic Agonists

Medically reviewed by Drugs.com on Jun 10, 2024. Written by ASHP.

Introduction

Relatively selective α2-adrenergic agonist;1 4 7 12 19 43 62 65 imidazoline-derivative sympathomimetic amine.a

Uses for Apraclonidine (EENT)

Inhibition of Perioperative IOP Increases

Apraclonidine 1% is used prophylactically to prevent or reduce intraoperative and postoperative increases in intraocular pressure (IOP) before and after ocular laser surgery (e.g., argon laser trabeculoplasty, argon laser iridotomy, neodymium yttrium aluminum garnet [Nd:YAG] laser posterior capsulotomy).1 2 16 17 18 19 20

Glaucoma

Apraclonidine 0.5% is used for short-term (<1 month) adjunctive therapy in patients with open-angle glaucoma receiving maximally tolerated drug therapy (i.e., a topical β-adrenergic blocking agent in conjunction with a systemically administered carbonic anhydrase inhibitor and a sympathomimetic and/or a parasympathomimetic agent) who require additional reduction in IOP.62 65

Apraclonidine (EENT) Dosage and Administration

Administration

For topical ophthalmic use only.62 Not for injection or oral use.62

Ophthalmic Administration

Apply topically to the affected eye(s) as an ophthalmic solution.1 2 16 17 18 19 20 54 62

Avoid contamination of the solution container.34 62

If more than one topical ophthalmic drug is used, administer the drugs at least 5 minutes apart.c

1% solution is for single use only; use a separate container for each single-drop dose of 1% solution and discard each container after use.b

Dosage

Available as apraclonidine hydrochloride; dosage expressed in terms of apraclonidine.1 a

Adults

Inhibition of Perioperative IOP Increases
Ophthalmic

Apraclonidine 1% solution: 1 drop in the eye undergoing surgery 1 hour before surgery; instill 1 drop in the same eye immediately upon completion of surgery.1 16 17 18 19

Glaucoma
Ophthalmic

Apraclonidine 0.5% solution: 1 or 2 drops in the affected eye(s) 3 times daily.62 65 Benefit of therapy for most patients is <1 month.62 65 (See Tachyphylaxis under Cautions.)

Special Populations

No special population dosage recommendations at this time.b c

Detailed Apraclonidine ophthalmic dosage information

Cautions for Apraclonidine (EENT)

Contraindications

Concomitant use with an MAO inhibitor.62 (See Specific Drugs under Interactions.)

Known hypersensitivity to apraclonidine, clonidine, or to any ingredient in the formulation.1 62

Warnings/Precautions

Sensitivity Reactions

Hypersensitivity Reactions

Topical hypersensitivity reactions (e.g., hyperemia, pruritus, discomfort, tearing, foreign body sensation, eyelid swelling) reported.36 62 65 c If hypersensitivity reaction occurs, discontinue apraclonidine.c

General Precautions

Systemic Effects

Perioperative use of apraclonidine hydrochloride ophthalmic solution to date has been associated with a low potential for causing adverse systemic effects;1 2 16 17 18 19 29 36 48 however, continuous (e.g., up to 12 weeks) use of apraclonidine ophthalmic solution has been associated with a higher incidence of adverse systemic effects.62

Cardiovascular Effects

Possible adverse cardiovascular effects (e.g., bradycardia,1 29 chest heaviness or burning,1 palpitation,1 reduced systolic and diastolic BP,2 29 orthostatic hypotension).1 57

Use with caution in patients with severe uncontrolled cardiac disease (e.g., hypertension), coronary insufficiency, recent MI, cerebrovascular disease, Raynaud’s disease, or thromboangitis obliterans.1 62 65

Use with caution in patients with a history of vasovagal attacks; 1 possible vasovagal attacks during laser surgery.1 17

Depressive Episodes

Carefully supervise patients with a history of mental depression; may be subject to further depressive episodes.62

CNS Effects

Possible dizziness and somnolence; performance of activities requiring mental alertness and physical coordination may be impaired.62

Tachyphylaxis

IOP-lowering efficacy may diminish during therapy with 0.5% ophthalmic solution; careful monitoring recommended.c

Patient Monitoring

Closely monitor patients who develop excessive IOP reduction.1

Periodic visual field tests and frequent follow-up examinations recommended in patients receiving maximally tolerated drug therapy and 0.5% apraclonidine for glaucoma to delay surgery;62 discontinue therapy if IOP increases substantially.62

Ocular Effects

Abnormal vision, pain, keratitis, keratopathy, blepharitis, blepharoconjunctivitis, photophobia, corneal staining, corneal erosion, corneal infiltrate, and irritation reported rarely.62 65

Specific Populations

Pregnancy

Category C.b c

Lactation

Not known whether apraclonidine is distributed into milk.1 62 Caution advised if 0.5% ophthalmic solution is used.62 Temporarily discontinue nursing during the day that 1% ophthalmic solution is used for inhibition of perioperative IOP increases.1

Pediatric Use

Safety and efficacy not established in children <21 years of age.1 57

Geriatric Use

No substantial differences in safety and efficacy relative to younger adults.b c

Hepatic Impairment

Closely monitor cardiovascular parameters in patients with impaired liver function.c

Renal Impairment

Elimination may be decreased; closely monitor cardiovascular parameters in severe renal impairment.62

Use with caution in patients with chronic renal impairment.c

Common Adverse Effects

0.5% solution: Discomfort, hyperemia, pruritus, tearing, lid edema, dry mouth, foreign body sensation, blanching, blurred vision, conjunctivitis, discharge, dry eye.c

1% solution: Ocular injection, upper lid elevation, irregular heart rate, nasal decongestion, ocular inflammation, conjunctival blanching, mydriasis.b

Drug Interactions

Specific Drugs

Drug

Interaction

Comments

Antidepressants, tricyclic (imipramine, desipramine)

Potential decrease in IOP-lowering effect62

Use concomitantly with caution62

Antipsychotic agents

Possible additive hypotensive effects62

Reported with concomitant systemic clonidine therapy; not evaluated with concomitant apraclonidine therapy1 62

Cardiac glycosides

Possible decrease in heart rate and BP62

Use concomitantly with caution62

CNS depressants (e.g., barbiturates, opiates, anesthetics, sedatives, alcohol)

Possible additive CNS effects62

Hypotensive agents

Possible decrease in heart rate and BP62

Use concomitantly with caution62

MAO inhibitors

Possible excess of circulating catecholamines with withdrawal of apraclonidine62

Concomitant use contraindicatedb c

No data available on the circulating plasma concentrations of catecholamines following apraclonidine withdrawal62

Ocular hypotensive agents

Additive IOP-lowering effect16 17

Used to therapeutic advantage16 17 18
Apraclonidine ophthalmic drug interactions (more detail)

Apraclonidine (EENT) Pharmacokinetics

Absorption

Bioavailability

Some systemic absorption occurs following topical administration.1 2 15 29 62

Onset

Following topical application of a 1% solution, reduction in IOP usually occurs within 1 hour and reaches a maximum within 3–5 hours.1 2 16 17 62

Duration

Reduction in IOP persists for at least 12 hours.1 2 16 17 62

Distribution

Extent

Distribution into both ocular and systemic human tissues is unknown.52

Not known whether apraclonidine crosses the placenta or is distributed into milk.1 57 62

Elimination

Metabolism

Metabolic fate not fully elucidated.57 58 62

Elimination Route

Elimination characteristics not fully elucidated.57 58 62

Half-life

0.5% solution: 8 hours.62 65

Stability

Storage

Ophthalmic

Solution

0.5% solution: Tight, light-resistant container at 2–27°C; do not freeze.62

1% solution: Tight, light-resistant container at 2–25°C.1 b

Actions

Advice to Patients

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Apraclonidine Hydrochloride

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Ophthalmic

Solution

0.5% (of apraclonidine)

Iopidine (with benzalkonium chloride)

Alcon

1% (of apraclonidine)

Iopidine (with benzalkonium chloride)

Alcon

AHFS DI Essentials™. © Copyright 2025, Selected Revisions June 10, 2024. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

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a. AHFS drug information 2006. McEvoy GK, ed. Apraclonidine. Bethesda, MD: American Society of Health-System Pharmacists; 2830-3.

b. Alcon Laboratories. Iopidine (apraclonidine hydrochloride ophthalmic solution) 1% prescribing information. Fort Worth, TX; 2004 Dec.

c. Alcon Laboratories. Iopidine (apraclonidine ophthalmic solution) 0.5% prescribing information. Fort Worth, TX; 2003 Dec.

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