Action

Selectively antagonizes H₁ and inhibits release of histamine and other mediators from cells (such as mast cells) involved in allergic response. Based on in vitro studies using human cell lines, inhibition of other mediators involved in allergic reactions (such as leukotrienes and platelet-aggregating factor) has also been demonstrated. Decreased chemotaxis and activation of eosinophils has also been demonstrated.

Availability

Nasal spray (Astepro): 0.15% (205.5 mcg in each 0.137-ml spray)

Nasal spray, metered (Astelin): 137-mcg spray

Ophthalmic solution (Optivar): 0.05%

Indications and dosages

➣ Seasonal and allergic rhinitis

Adults and children age 12 and older: 1 or 2 sprays (Astelin, Astepro) per nostril b.i.d. or 2 sprays (Astepro) per nostril once daily

Children ages 5 to 11: 1 spray (Astelin) per nostril b.i.d.

➣ Perennial allergic rhinitis, vasomotor rhinitis

Adults and adolescents age 12 and older: 2 sprays (Astelin) per nostril b.i.d.

➣ Allergic conjunctivitis

Adults and adolescents age 3 and older: 1 drop (Optivar) in each eye b.i.d.

Contraindications

• Hypersensitivity to drug or its components (Astelin, Optivar)

• None (Astepro)

Precautions

Use cautiously in:

• concurrent use of alcohol and CNS depressants (avoid Astepro use)

• pregnant or breastfeeding patients

• children (safety and efficacy not established for those younger than age 3 [Optivar]; age 5 [Astelin]; age 12 [Astepro]).

Administration

• Follow manufacturer's directions and prime Astelin nasal spray before use.

• Prime Astepro nasal spray before initial use and when it hasn't been used for 3 or more days.

• Be aware that patient shouldn't wear contact lenses when the eyes are red and that Optivar shouldn't be used to treat redness caused by contact lenses.

• Wait 10 minutes before allowing patient to put soft contact lenses back in after Optivar administration, because the preservative benzalkonium chloride may be absorbed.

Adverse reactions

CNS: dizziness (with Astelin); headache, fatigue, somnolence (with Astelin, Astepro)

EENT: transient eye burning or stinging (with Optivar); nasal burning, nasal discomfort, sneezing (with Astepro); pharyngitis, paroxysmal sneezing, rhinitis, epistaxis (with Astelin)

GI: nausea, dry mouth (with Astelin); nasal discomfort (with Astepro); epistaxis (with Astelin, Astepro)

Other: weight increase (with Astelin); bitter taste

Interactions

Drug-drug. Cimetidine: increased mean C_max and area under the curve of orally administered azelastine

CNS depressants: additional decreased alertness and impairment of CNS performance (with Astelin, Astepro)

Drug-behaviors. Alcohol use: decreased alertness and impairment of CNS performance (with Astelin, Astepro)

Patient monitoring

• Monitor patient for bothersome adverse reactions.

Patient teaching

• Instruct patient on proper use of nasal spray and eyedrops.

• Advise patient to avoid other antihistamines, alcohol, and other CNS depressants such as sedatives while using nasal spray.

• Instruct patient to avoid spraying nasal spray into the eyes.

• Advise patient not to wear contact lenses if the eyes are red. Instruct the patient who wears soft contact lenses and whose eyes aren't red to wait at least 10 minutes after instilling eye-drops before inserting contact lenses.

• Caution patient to avoid driving and other hazardous activities until drug's effects on concentration and alertness are known.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs and behaviors mentioned above.