Azelastine hydrochloride

How it works

It selectively antagonises peripheral histamine H1 receptors and stabilises mast cells, reducing the histamine-driven allergic response in the nasal and ocular mucosa.

Prescribing in practice

• Applied topically it acts locally with rapid onset and limited systemic absorption, so systemic antihistamine effects are uncommon at recommended use.
• A bitter or altered taste is a characteristic and common adverse effect of the nasal spray, which may affect adherence.
• Mild local irritation, nasal stinging or transient eye irritation may occur with the respective formulations.

Monitoring

No routine laboratory monitoring is required; assess symptom control and local tolerability at review.

Counselling the patient

• A bitter taste after using the nasal spray is common and can be reduced by keeping the head tilted forward and not sniffing hard.
• Use regularly during the allergy season for best effect.
• Tell your team if local irritation is troublesome or symptoms are not controlled.

Evidence & guidelines

Topical antihistamines such as azelastine are established options for allergic rhinitis and conjunctivitis, providing rapid local symptom relief in line with allergy guidance.