Brand names: Astelin, Optivar
Drug class: Antiallergic Agents
- Histamine H1-receptor Antagonists
VA class: OP900
Molecular formula: C₂₂H₂₄ClN₃O•ClH
CAS number: 79307-93-0

Introduction

Relatively selective histamine H₁-receptor antagonist;^{1 2} a phthalazinone derivative.^{1 2 11 13 21 24 25 27}

Uses for Azelastine

Seasonal Allergic Rhinitis

Symptomatic treatment of seasonal allergic rhinitis (e.g., hay fever).^{1 11} Intranasal azelastine is at least as effective as oral antihistamines (e.g., cetirizine) or intranasal corticosteroids.^{16 17 18 19 20 21 22 23 24 27 28} May provide improvement of ocular manifestations, possibly secondary to systemic absorption of the drug.^{16 19 21 22 24 27}

Nonallergic Rhinitis

Symptomatic treatment of nonallergic (vasomotor) rhinitis.^a

Allergic Conjunctivitis

Symptomatic relief of ocular itching associated with allergic conjunctivitis.^{2 30 31}

Related/similar drugs

prednisone, cetirizine ophthalmic, dexamethasone ophthalmic, prednisolone ophthalmic, doxylamine, Deltasone

Azelastine Dosage and Administration

Administration

Administer nasal solution intranasally twice daily, using a spray pump.^{1 11}

Apply ophthalmic solution topically to the eye twice daily. ² Ophthalmic solution is not for injection or oral use.²

Intranasal Administration

Before initial use, prime the pump until a fine mist appears, using up to 4 actuations of the pump.^{1 11 14} Administration of solution in a stream of liquid rather than as a mist may fail to provide maximum benefit and may cause discomfort.¹⁴

If inhaler has not been used for ≥3 days, reprime pump with 2 actuations or until a fine mist appears.¹⁴ Reprime pump when the spray pump is inserted into the second bottle.¹⁴

To actuate the pump, hold the bottle in one hand, with 2 fingers on the shoulders of the pump unit and the thumb on the bottom of the bottle.¹⁴ Press the bottom firmly and rapidly upward with the thumb to produce a fine mist.¹⁴

Prior to administration, gently blow the nose to clear nasal passages.¹⁴ Insert nasal spray tip ¼ to ½ inch into a nostril, tilt head slightly forward while holding the bottle vertically upright, and aim spray tip toward the back of the nose.¹⁴ Rapidly and firmly press and actuate pump into the nostril while holding the other nostril closed, gently sniffing at the same time;¹⁴ do not tilt head back after dosing.¹⁴

Repeat procedure for the other nostril.¹⁴ Provide a second spray into each nostril, beginning with the first nostril.¹⁴ Alternate nostrils between each actuation of nasal spray.¹⁴

Use caution to avoid spraying nasal spray into the eyes.^{1 11 14}

Ophthalmic Administration

Remove soft contact lenses prior to administration of each dose (since benzalkonium chloride may be absorbed by the lenses); may reinsert lenses 10 minutes after administration if eyes are not red.²

Avoid contamination of the solution container.²

Dosage

Available as azelastine hydrochloride; dosage expressed in terms of the salt.^{1 2 14}

When properly primed, the nasal spray pump delivers approximately 100 metered doses per bottle.^{1 16}

Pediatric Patients

Seasonal Allergic Rhinitis

Intranasal

Children ≥12 years of age: 2 sprays (274 mcg) in each nostril twice daily.^{1 11 16}

Children 5–11 years of age: 1 spray (137 mcg) in each nostril twice daily.¹

Nonallergic Rhinitis

Intranasal

Children ≥12 years of age: 2 sprays (274 mcg) in each nostril twice daily.^a

Allergic Conjunctivitis

Ophthalmic

Children ≥3 years of age: 1 drop of a 0.05% solution in the affected eye(s) twice daily.²

Adults

Seasonal Allergic Rhinitis

Intranasal

2 sprays (274 mcg) in each nostril twice daily.^{1 11 16}

Nonallergic Rhinitis

Intranasal

2 sprays (274 mcg) in each nostril twice daily.^a

Allergic Conjunctivitis

Ophthalmic

1 drop of a 0.05% solution in the affected eye(s) twice daily.²

Special Populations

Geriatric Patients

Cautious dosing of nasal solution recommended.^a

Cautions for Azelastine

Contraindications

• Known hypersensitivity to azelastine or any ingredient in the formulation.^{a b}

Warnings/Precautions

General Precautions

CNS Effects

Somnolence reported in patients receiving azelastine nasal solution.^{1 16 19 22 24 26 28} Performance of activities requiring mental alertness and physical coordination may be impaired.^a

Concurrent use of nasal solution with other CNS depressants may potentiate CNS depression.^a (See Specific Drugs under Interactions.)

Specific Populations

Pregnancy

Category C.^{a b}

Lactation

Not known whether azelastine is distributed into milk.^{a b} Use with caution in nursing women.^{a b}

Pediatric Use

Safety and efficacy of nasal solution for treatment of seasonal allergic rhinitis not established in children <5 years of age;¹ safety and efficacy for treatment of nonallergic rhinitis not established in children <12 years of age.^a

Safety and efficacy of ophthalmic solution not established in children <3 years of age.²

Geriatric Use

Response to nasal solution does not appear to differ from that in younger adults.^a

No substantial differences in safety and efficacy of ophthalmic solution relative to younger adults.^b

Common Adverse Effects

Nasal solution: Transient nasal burning or stinging,¹⁴ bitter taste, somnolence, headache, pharyngitis, paroxysmal sneezing.^{1 16 19 22 24 26 28}

Ophthalmic solution: Transient ocular burning/stinging, bitter taste, headache.^{2 30 31}

Drug Interactions

Metabolized by CYP isoenzymes.^a

Specific Drugs

Azelastine Pharmacokinetics

Absorption

Bioavailability

Following intranasal administration, systemic bioavailability is 40%.^{1 11 16} Peak plasma concentrations occur 2–3 hours after intranasal administration.^a

Absorption following ophthalmic administration is low.^b

Onset

Following intranasal administration, symptomatic relief is evident within 1 hour; substantial relief usually is apparent within 3 hours; peak effect occurs between 4–6 hours.^{1 11 13}

Following ophthalmic administration, onset of action is rapid (3 minutes).²

Duration

Following intranasal administration, effect persists throughout the 12-hour dosage interval.^{1 11 13}

Ophthalmic effect persists for about 8 hours.²

Distribution

Plasma Protein Binding

Azelastine: Approximately 88%.^a

N-desmethylazelastine: 97%.^a

Elimination

Metabolism

Metabolized primarily to N-desmethylazelastine (an active metabolite) by CYP isoenzymes.^a

Elimination Route

Approximately 75% of an oral dose is excreted in feces, with <10% as unchanged drug.^a

Half-life

Azelastine: 22 hours (following oral and IV administration).^a

N-desmethylazelastine: 54 hours.^a

Special Populations

In patients with hepatic impairment, pharmacokinetics not altered.^a

Stability

Storage

Nasal

Solution

20–25°C.^a Protect from freezing.^a

Discard both bottles 3 months after initial insertion of the spray pump into the first of the 2 bottles in the dispensing package.¹⁴

Ophthalmic

Solution

20–25°C.^b Store upright.^b

Actions

• Inhibits the release of histamine^a and other mediators (e.g., leukotrienes, platelet activating factor [PAF]) involved in allergic reactions.^{2 29}

• May inhibit the accumulation of eosinophils at the site of allergic inflammation and prevent eosinophil degranulation.^{1 29}

Advice to Patients

• Proper techniques for assembly and priming of nasal spray pump and for administration of the nasal solution.¹ Importance of not administering the entire dose (i.e., 4 sprays) into a single nostril.^{2 14} Give patients a copy of the manufacturer’s patient instructions.^{1 11 14}

• Importance of learning and adhering to proper administration techniques to avoid contamination of the ophthalmic solution container.²

• Importance of removing soft contact lenses prior to administration of each ophthalmic dose.² May reinsert contact lenses 10 minutes after administration if eyes are not red; do not wear contact lenses if eye(s) are red.² Not indicated for contact lens-related irritation.²

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.^a

• Potential for intranasal azelastine to impair mental alertness or physical coordination; use caution when driving or operating machinery until effects on individual are known.^a Avoid concomitant use of alcohol-containing beverages or products.¹

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.^a

• Importance of informing patients of other important precautionary information.^a (See Cautions.)

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.

Medical Disclaimer