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Medically reviewed by Last updated on Nov 7, 2020.


(a pra KLOE ni deen)

Index Terms

  • Aplonidine
  • Apraclonidine HCl
  • Apraclonidine Hydrochloride
  • p-Aminoclonidine

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Solution, Ophthalmic:

Iopidine: 0.5% (5 mL [DSC], 10 mL [DSC]); 1% (24 ea) [contains benzalkonium chloride]

Generic: 0.5% (5 mL, 10 mL)

Brand Names: U.S.

  • Iopidine

Pharmacologic Category

  • Alpha2 Agonist, Ophthalmic


Apraclonidine is a potent alpha-adrenergic agent similar to clonidine; relatively selective for alpha2-receptors but does retain some binding to alpha1-receptors; appears to result in reduction of aqueous humor formation; its penetration through the blood-brain barrier is more polar than clonidine which reduces its penetration through the blood-brain barrier and suggests that its pharmacological profile is characterized by peripheral rather than central effects.

Onset of Action

1 hour; Peak effect: Decreased intraocular pressure: 3 to 5 hours

Half-Life Elimination

Systemic: 0.5% solution: 8 hours

Use: Labeled Indications

Elevated intraocular pressure:

0.5% solution: Short-term, adjunctive therapy in patients who require additional reduction of intraocular pressure (IOP)

1% solution: Prevention and treatment of postsurgical IOP elevation following argon laser trabeculoplasty, argon laser iridotomy or Nd:YAG posterior capsulotomy (manufacturer's labeling) or as part of a 4-drug medical management regimen in acute angle-closure glaucoma when the patient cannot be seen by an ophthalmologist for ≥1 hour (off-label use) (Krawitz 1990; Pokhrel 2007).


Hypersensitivity to apraclonidine, clonidine, or any component of the formulation; concomitant use with MAO inhibitors.

Canadian labeling: Additional contraindications (not in US labeling): Children and adolescents <18 years old.

Dosing: Adult

Elevated intraocular pressure: Ophthalmic:

Open-angle glaucoma: 0.5%: Instill 1 to 2 drops into the affected eye(s) 3 times daily.

Angle-closure glaucoma (off-label use): 1%: Instill 1 drop into the affected eye as part of a 4-drug regimen; may repeat in 30 to 60 minutes if intraocular pressure (IOP) remains elevated (eg, >40 mm Hg). Note: Reserve medical management for emergency situations when an assessment by an ophthalmologist will be delayed by ≥1 hour (Krawitz 1990; Pokhrel 2007).

Prevention and treatment of postsurgical IOP elevation: 1%: Instill 1 drop into the operative eye 1 hour prior to anterior segment laser surgery, second drop in same eye immediately upon completion of procedure.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Geriatric

Refer to adult dosing.


Ophthalmic: For topical ophthalmic use only; not for injection or oral administration.

0.5% solution: Wait 5 minutes between instillation of other ophthalmic agents to avoid washout of previous dose. After topical instillation, finger pressure should be applied to lacrimal sac to decrease drainage into the nose and throat and minimize possible systemic absorption.

1% solution: Use a separate container for each single drop dose; discard container after each use. When treating acute angle-closure glaucoma, separate administration of other ophthalmic agents by ≥1 minute (Pokhrel 2007).


Iopidine 0.5%: Store between 2°C to 27°C (36°F to 80°F); protect from freezing and light.

Iopidine 1%: Store between 2°C to 25°C (36°F to 77°F); protect from light.

Drug Interactions

Mianserin: May diminish the therapeutic effect of Alpha2-Agonists (Ophthalmic). Avoid combination

Mirtazapine: May diminish the antihypertensive effect of Alpha2-Agonists. Management: Consider avoiding concurrent use. If the combination cannot be avoided, monitor for decreased effects of alpha2-agonists if mirtazapine is initiated/dose increased, or increased effects if mirtazapine is discontinued/dose decreased. Consider therapy modification

Monoamine Oxidase Inhibitors: May enhance the adverse/toxic effect of Apraclonidine. Monoamine Oxidase Inhibitors may increase the serum concentration of Apraclonidine. Avoid combination

Tricyclic Antidepressants: May diminish the therapeutic effect of Alpha2-Agonists (Ophthalmic). Monitor therapy

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

Frequency not always defined.

5% to 15%:

Gastrointestinal: Xerostomia (10%)

Ophthalmic: Eye discomfort, eye pruritus, ocular hyperemia

1% to 5%:

Cardiovascular: Cardiac arrhythmia (<3%), chest pain (<3%), facial edema (<3%), peripheral edema (<3%), localized blanching

Central nervous system: Altered sense of smell (<3%), ataxia (<3%), depression (<3%), dizziness (<3%), drowsiness (<3%), headache (<3%), insomnia (<3%), malaise (<3%), nervousness (<3%), paresthesia (<3%)

Dermatologic: Contact dermatitis (<3%), dermatitis (<3%)

Gastrointestinal: Constipation (<3%), dysgeusia (<3%), nausea (<3%)

Neuromuscular & skeletal: Myalgia (<3%), weakness (<3%)

Ophthalmic: Blurred vision, conjunctivitis, dry eye syndrome, eyelid edema, eye discharge, foreign body sensation of eye, lacrimation

Respiratory: Asthma (<3%), dry nose (<3%), dyspnea (<3%), pharyngitis (<3%), rhinitis (<3%)

<1%, postmarketing, and/or case reports: Blepharitis, blepharoconjunctivitis, bradycardia, conjunctival edema, corneal erosion, corneal infiltrates, corneal staining, crusting of eyelid, epithelial keratopathy, erythema of eyelid, eyelid disease, eyelid retraction, eye irritation, eye pain, follicular conjunctivitis, hypersensitivity reaction, keratitis, ocular edema, photophobia, scaling of eyelid, visual disturbance


Concerns related to adverse effects:

• CNS effects: May cause dizziness and somnolence, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).

• Hypersensitivity reactions: Use may lead to allergic-like reactions, including hyperemia, pruritus, discomfort, tearing, foreign body sensation, and edema of the lid and conjunctiva; if these symptoms occur, discontinue use.

Disease-related concerns:

• Cardiovascular disease: Use with caution in patients with severe uncontrolled cardiovascular disease (eg, hypertension), coronary insufficiency, recent myocardial infarction, cerebrovascular disease, Raynaud disease, and thromboangiitis obliterans.

• Hepatic impairment: Close monitoring of cardiovascular parameters is recommended in patients with hepatic impairment; clonidine (structurally related to apraclonidine) administered systemically undergoes partial hepatic metabolism.

• Renal impairment: Close monitoring of cardiovascular parameters is recommended in patients with renal impairment; use with caution in patients with chronic renal failure. Topical apraclonidine has not been studied in patients with renal impairment; however, the half-life of clonidine (structurally related to apraclonidine) administered systemically is increased significantly in severe impairment.

• Vasovagal reactions: Potential for a vasovagal attack to occur; use with caution in patients with history of vasovagal reactions.

Special populations:

• Contact lens wearers: Some products contain benzalkonium chloride which may be absorbed by soft contact lenses; contact lenses should be removed during instillation; may be reinserted 15 minutes after instillation.

Other warnings/precautions:

• Appropriate use: For topical ophthalmic use only; not for injection or oral administration.

• Tachyphylaxis: The IOP-lowering efficacy may decrease over time in some patients; most patients experience a benefit for less than one month; routinely monitor IOP.

Monitoring Parameters

Closely monitor patients who develop exaggerated reductions in intraocular pressure; visual fields (periodically for glaucoma patients on maximally tolerated medical therapy using 0.5% solution to delay surgery); tachyphylaxis; cardiovascular parameters in patients with renal and/or hepatic impairment; depression in depressed patients. Check intraocular pressure 30 to 60 minutes after administration for acute use of 1% solution for acute angle-closure glaucoma (Pokhrel 2007).

Pregnancy Considerations

Adverse events have been observed in animal reproduction studies. If ophthalmic agents are needed during pregnancy, the minimum effective dose should be used in combination with punctal occlusion to decrease potential exposure to the fetus (Samples 1988).

Patient Education

What is this drug used for?

• It is used to lower high eye pressure.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Blurred vision

• Dry eyes

• Increased tears

• Dizziness

• Fatigue

• Dry mouth

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Vision changes

• Eye pain

• Severe eye irritation

• Eyelid swelling

• Eye discharge

• Foreign body sensation in eye

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.