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Levobunolol (Monograph)

Brand name: Betagan
Drug class: beta-Adrenergic Blocking Agents
- Beta-Adrenergic Blocking Agents
- β-Adrenergic Blocking Agents
VA class: OP101
Chemical name: (-)-5-(3-tert-Butylamino-2-hydroxypropoxy)-1,2,3,4-tetrahydronaphthalen-1-one hydrochloride
Molecular formula: C17H25NO3•ClH [Molecular Formula]
CAS number: 27912-14-7[CAS number]

Medically reviewed by Drugs.com on Nov 21, 2023. Written by ASHP.

Introduction

Nonselective β-adrenergic blocking agent.1 2 3 9 11 12 13 14 15 16 17 20 21 22 23 27 28

Uses for Levobunolol

Ocular Hypertension and Glaucoma

Reduction of elevated IOP in patients with chronic open-angle glaucoma1 2 51 52 53 54 55 56 58 92 113 or ocular hypertension.1 2 51 52 53 54 55 56 57 58 92 113 When administered twice daily, usual dosages of levobunolol are as effective as usual dosages of timolol in reducing IOP.2 51 52 54 55 56 58 92

When selecting an initial ocular hypotensive agent, consider extent of the required IOP reduction, coexisting medical conditions, and drug characteristics (e.g., dosing frequency, adverse effects, cost).130 132 With single-agent regimens, the reduction in IOP is approximately 25–33% with topical prostaglandin analogs; 20–25% with topical β-adrenergic blocking agents, α-adrenergic agonists, or miotic (parasympathomimetic) agents; 20–30% with oral carbonic anhydrase inhibitors; 18% with topical rho kinase inhibitors; and 15–20% with topical carbonic anhydrase inhibitors.130 131

A prostaglandin analog frequently is considered for initial therapy in the absence of other considerations (e.g., contraindications, cost considerations, intolerance, adverse effects, patient refusal) because of relatively greater activity, once-daily administration, and low frequency of systemic adverse effects; however, ocular adverse effects can occur.130 131 132 134

Goal is to maintain an IOP at which visual field loss is unlikely to substantially reduce quality of life during the patient's lifetime.130 132

Reduction of pretreatment IOP by ≥25% shown to slow progression of primary open-angle glaucoma.130 131 Set an initial target IOP (based on extent of optic nerve damage and/or visual field loss, baseline IOP at which damage occurred, rate of progression, life expectancy, and other considerations) and reduce IOP toward this goal.130 131 132 Adjust target IOP up or down as needed over course of disease.130 131 132

Combination therapy with drugs from different therapeutic classes often required to control IOP.131 133

Levobunolol Dosage and Administration

General

Administration

Ophthalmic Administration

Apply topically to the eye as an ophthalmic solution.1 2 51 52 53 54 55 56 57 58 92 113

Avoid contamination of the solution container.80 (See Bacterial Keratitis under Cautions.)

Remove soft contact lenses before administering each dose; may reinsert lenses 15 minutes after the dose.1 113 (See Contact Lenses under Cautions.)

Dosage

Available as levobunolol hydrochloride; dosage expressed in terms of the salt.1 113

Adults

Ocular Hypertension and Glaucoma
Ophthalmic

Initially, 1 or 2 drops of a 0.5% ophthalmic solution in the affected eye(s) once daily1 2 51 52 53 54 55 56 58 92 93 or, alternatively, 1 or 2 drops of a 0.25% ophthalmic solution twice daily.113

May increase dosage, if necessary, to 1 drop of a 0.5% ophthalmic solution in the affected eye(s) twice daily in patients with more severe or uncontrolled glaucoma.1

If target IOP not achieved, may initiate additional or alternative ocular hypotensive agents.130 131 133 (See Ocular Hypertension and Glaucoma under Uses.) Generally avoid concomitant use of multiple topical ophthalmic β-adrenergic blocking agents.1

Prescribing Limits

Adults

Ocular Hypertension and Glaucoma
Ophthalmic

Dosages >1 drop of a 0.5% ophthalmic solution twice daily generally have not been more effective.1

Cautions for Levobunolol

Contraindications

Cardiogenic shock or overt cardiac failure1 that is not adequately compensated.98 99 (See Cardiac Failure under Cautions.)

Asthma, history of asthma, or severe COPD (e.g., severe chronic bronchitis or emphysema).1 (See Respiratory Disease under Cautions.)

Sinus bradycardia1 52 or AV block greater than first degree.1 18

Known hypersensitivity to levobunolol or any ingredient in the formulation.1

Warnings/Precautions

Sensitivity Reactions

History of Anaphylactic or Hypersensitivity Reactions

Patients with a history of severe anaphylactic reaction to a variety of allergens may be more reactive to repeated accidental, diagnostic, or therapeutic challenges with such allergens while taking β-adrenergic blocking agents; such patients may be unresponsive to usual doses of epinephrine used to treat anaphylactic reactions.1

Use with caution in patients with known hypersensitivity to other β-adrenergic blocking agents.1

Sulfite Sensitivity

Levobunolol hydrochloride ophthalmic solution contains sulfites, which may cause allergic-type reactions (including anaphylaxis and life-threatening or less severe asthmatic episodes) in certain susceptible individuals.1 82 83 84 85 86 87 88 89 110 113 d

Systemic Effects

May be absorbed systemically following topical application to the eye;1 2 consider the usual precautions associated with systemic use of β-adrenergic blocking agents when using topical levobunolol.1

Hypotension

Ophthalmic β-adrenergic blocking agents may impair compensatory increases in heart rate and increase risk of hypotension.1

Cardiac Failure

Severe cardiac reactions, including death associated with cardiac failure, reported in patients receiving topical (ocular) β-adrenergic blocking agents.1 May precipitate more severe cardiac failure in patients with preexisting heart failure and may cause cardiac failure in some patients without a history of heart failure.1 (See Actions.)

Contraindicated in patients with cardiogenic shock or with overt cardiac failure1 that is not adequately compensated (e.g., treated with cardiac glycosides and/or diuretics).98 99 In patients without a history of cardiac failure, discontinue therapy at the first sign or symptom of cardiac failure.1

Respiratory Disease

Severe respiratory reactions, including death resulting from bronchospasm, reported in patients with asthma receiving topical (ocular) β-adrenergic blocking agents.1

Contraindicated in patients with asthma, history of asthma, or severe COPD (e.g., severe chronic bronchitis or emphysema).1 Patients with mild or moderately severe COPD, bronchospastic disease other than asthma, or a history of such bronchospastic disease generally should not receive β-adrenergic blocking agents.1 If levobunolol is required, use with caution in such patients since it may antagonize bronchodilation produced by endogenous and exogenous catecholamines.1

Use with caution in other patients with diminished pulmonary function.1

Major Surgery

Possible increased risks associated with general anesthesia (e.g., severe hypotension, difficulty restarting or maintaining heart beat) due to decreased ability of the heart to respond to reflex β-adrenergic stimuli.1

Need for withdrawal of β-adrenergic blocking agents prior to major surgery is controversial; in some patients, gradual withdrawal of β-adrenergic blocking agents prior to elective surgery may be appropriate.1 60 93

If necessary during surgery, may reverse effects of β-adrenergic blocking agents by administering sufficient doses of β-adrenergic agonists (e.g., isoproterenol, dopamine, dobutamine, norepinephrine).1

Diabetes Mellitus

β-Adrenergic blocking agents may mask signs and symptoms of acute hypoglycemia; administer with caution in patients subject to spontaneous hypoglycemia and in diabetic patients (especially those with labile diabetes) who are receiving hypoglycemic agents.1 64

Thyrotoxicosis

β-Adrenergic blocking agents may mask signs of hyperthyroidism (e.g., tachycardia).1

Possible thyroid storm if β-adrenergic blocking agent is abruptly withdrawn; carefully monitor patients suspected of developing thyrotoxicosis.1

Choroidal Detachment

Choroidal detachment after filtration procedures reported with the administration of aqueous suppressant therapy.1

Vascular Insufficiency

Caution advised in patients with cerebrovascular insufficiency due to the potential effects of β-adrenergic blocking agents on BP and pulse.1 Consider alternative therapy if signs or symptoms of reduced cerebral blood flow occur.1

Caution also advised in patients with other syndromes associated with vascular insufficiency (i.e., Raynaud phenomenon); levobunolol may potentiate these syndromes.1

Angle-closure Glaucoma

Levobunolol has little or no effect on pupil size.1 2 51 52 53 54 55 56 58 Do not use alone in patients with angle-closure glaucoma; use only in combination with a miotic in these patients.1 7 98 104 105 106 107 108

Muscle Weakness

β-Adrenergic blocking agents reported to potentiate muscle weakness consistent with certain myasthenic manifestations (e.g., diplopia, ptosis, generalized weakness).1

Bacterial Keratitis

Bacterial keratitis reported with use of multiple-dose containers of topical ophthalmic solutions.114 Containers were inadvertently contaminated by patients, most of whom had concurrent corneal disease or disruption of the ocular epithelial surface.114

Improper handling of ophthalmic solutions can result in contamination of the solution by common bacteria known to cause ocular infections.114 Serious damage to the eye and subsequent loss of vision may result from using contaminated ophthalmic preparations.114 (See Advice to Patients.)

Contact Lenses

Levobunolol ophthalmic solution contains benzalkonium chloride, which may be absorbed by soft contact lenses.1 113 Remove soft contact lenses before administering each dose; may reinsert lenses 15 minutes after the dose.1 113

Specific Populations

Pregnancy

No evidence of maternal toxicity or fetal harm in reproduction studies using oral levobunolol in rats.1 2 Fetotoxicity (increased resorptions) observed in rabbits (animals that may be particularly sensitive to β-adrenergic blocking agents).1 2

No adequate and controlled studies in pregnant women; use only if potential benefits justify the possible risks to the fetus.1

Lactation

Not known whether levobunolol is distributed into milk following topical application to the eye.1 Caution if used in nursing women.1

Pediatric Use

Safety and efficacy not established.1

Geriatric Use

No overall differences in safety and efficacy relative to younger adults.1

Common Adverse Effects

Ocular stinging1 2 52 53 58 or burning1 2 51 52 53 on instillation,1 2 51 52 53 58 blepharoconjunctivitis.1 2 51

Drug Interactions

Specific Drugs

Drug

Interaction

Comments

β-Adrenergic blocking agents, systemic or topical

Possible additive effects on IOP and/or systemic β-adrenergic blockade1

Caution recommended if used concomitantly with systemic β-adrenergic blocking agents1

Concomitant administration of multiple topical ophthalmic β-adrenergic blocking agents generally not recommended1

Calcium-channel blocking agents

Potential AV conduction disturbances, hypotension, and left ventricular failure1

Monitor for adverse cardiovascular effects during concomitant use1

Avoid concomitant use in patients with impaired cardiac function1

Cardiac glycosides

Potential additive effect in prolonging AV conduction time when β-adrenergic blocking agents, cardiac glycosides, and calcium-channel blocking agents (diltiazem, verapamil) used concomitantly1

Catecholamine-depleting drugs (e.g., reserpine)

Possible additive cardiovascular effects (e.g., hypotension, marked bradycardia); may be manifested as vertigo, syncope, or postural hypotension1

Observe closely1

Epinephrine

Possible mydriasis1

Atopic individuals and those with a history of severe anaphylactic reactions may not respond to usual doses of epinephrine used in the treatment of anaphylactic reactions1

Phenothiazines

Possible additive hypotensive effects caused by inhibition of phenothiazine and levobunolol metabolism1

Levobunolol Pharmacokinetics

Absorption

Bioavailability

Some systemic absorption occurs following topical administration.1 2 51 52 53 54 55 56 58 92

Onset

Following topical application to the eye, reduction in IOP is usually evident within 1 hour and reaches a maximum within about 2–6 hours.1 55 57 111

Duration

Reduction in IOP may persist for up to 24 hours.1 55 57 111

Distribution

Extent

Following topical application in rabbits, rapidly distributed throughout ocular tissues and fluids (e.g., cornea, iris, ciliary body, aqueous humor).2

Levobunolol crosses the placenta in some animals;2 not known whether distributed into human milk.1

Elimination

Metabolism

Extensively metabolized in the liver36 38 39 40 41 42 43 46 47 98 99 principally to dihydrolevobunolol, an active metabolite.36 38 39 40 42 44 45 46 47 48 99 109

Elimination Route

Approximately 93% of topically applied dose is excreted in urine and feces in rabbits.2 99

Half-life

Following ophthalmic administration of racemic bunolol in rabbits: 60–90 min.98 109

Stability

Storage

Ophthalmic

Solution

Light-resistant containers at 15–25°C.

Actions

Advice to Patients

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.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Levobunolol Hydrochloride

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Ophthalmic

Solution

0.25%*

Levobunolol Hydrochloride Ophthalmic Solution

0.5%*

Betagan

Allergan

Levobunolol Hydrochloride Ophthalmic Solution

AHFS DI Essentials™. © Copyright 2024, Selected Revisions December 1, 2020. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

References

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