Zalastin

For the treatment of both seasonal allergic rhinitis (e.g. hayfever) and perennial allergic rhinitis in patients aged 6 years and over.

Route of application is topical - nasal mucosa.

Adults

One application (0.14 ml) in each nostril twice daily (0.56 mg of azelastine hydrochloride).

Elderly

There have been no specific studies in the elderly.

Children

For children aged 6 years and older, one application (0.14 ml) in each nostril twice daily (0.56 mg of azelastine hydrochloride).

Proven allergy against azelastine hydrochloride.

None.

None.

The following frequencies of undesirable effects were reported:

Commonly (1 - 10 %), a substance-specific bitter taste may be experienced after administration (often due to incorrect method of application, namely tilting the head too far backwards during administration) which, in rare cases, may lead to nausea.

Uncommonly (0.1 - 1 %), a mild, transient irritation of the inflamed nasal mucosa may occur with symptoms such as stinging, itching, sneezing and epistaxis.

In very rare cases (< 0.01 %), hypersensitivity reactions (such as rash, pruritus, urticaria) were reported.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at:

www.mhra.gov.uk/yellowcard

The results of animal studies show that toxic doses can produce CNS symptoms, e.g. excitation, tremor, convulsions. Should these occur in humans, symptomatic and supportive treatment should be instigated as there is no specific antidote. Gastric lavage is recommended if the overdose is recent.

With the nasal route of administration overdosage reactions are not anticipated.

Azelastine, a phthalazinone derivative of novel structure, is classified as a potent long acting anti-allergic compound with particularly strong H1 antagonist properties.

Data from animal studies show that where high levels of azelastine are achieved both inhibition and release of chemical mediators (e.g. leukotriene, histamine, serotonin) involved in allergic reaction occurs.

After repeated nasal application (0.14 mg) into each nostril twice daily, the plasma levels of azelastine were about 0.26 ng/ml. The levels of the active metabolite desmethylazelastine were detected at or below the lower limit of quantification (0.12 ng/ml).

After repeated oral administration, the mean C_max steady state plasma levels were determined giving 3.9 ng/ml for azelastine and 1.86 ng/ml for desmethylazelastine after 2.2 mg b.i.d. azelastine which represents the therapeutic oral dose for the treatment of allergic rhinitis.

Following oral administration azelastine is rapidly absorbed showing an absolute bioavailability of 81%. Food has no influence on absorption. The volume of distribution is high indicating distribution predominantly to the peripheral tissues. The level of protein binding is low (80-95%, a level too low to give concern over drug displacement reactions).

Plasma elimination half lives after a single dose of azelastine are approximately 20 hours for azelastine and about 45 hours for N-desmethylazelastine (a therapeutically active metabolite). Excretion occurs mainly via the faeces. The sustained excretion of small amounts of the dose in the faeces suggest that some enterohepatic circulation may take place.

Nothing relevant.

None.

For separate bottle and pump

Open the bottle by unscrewing the cap. Place the spray pump nozzle in the bottle and screw the pump onto the bottle. Remove the protective cap. Before first using, squeeze down the collar several times until an even spray emerges. The Zalastin spray is now ready to use.

For attached pump and bottle

Remove the protective cap. Before first using, squeeze down the collar several times until an even spray emerges. The Zalastin spray is now ready to use.

Discard product six months after first opening.