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Topical antihistamine (H1)

Azelastine

Brand names: Rhinolast (nasal spray), Optilast (eye drops), Dymista (with fluticasone propionate)

Azelastine is a topical second-generation antihistamine available as a nasal spray and eye drops for allergic rhinitis and allergic conjunctivitis.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It selectively antagonises histamine H1 receptors and also has mast-cell stabilising and anti-inflammatory properties at the site of application.

Prescribing in practice

  • Patients may notice a transient bitter taste after nasal use, which can reduce adherence and is minimised by correct head-forward technique.
  • Onset of action is rapid, making it suitable for as-needed use in allergic symptoms.
  • It is also combined with a topical corticosteroid in some nasal preparations for more troublesome rhinitis.

Monitoring

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

Counselling the patient

  • Tilt the head slightly forward and breathe gently when spraying to reduce taste in the throat.
  • A bitter taste shortly after use is common and harmless.
  • Use regularly during the allergy season for best effect.

Evidence & guidelines

Topical antihistamines are recommended options for allergic rhinitis and conjunctivitis in NICE guidance.

Reference: SmPC Rhinolast / Optilast / Dymista; BSACI Rhinitis Guideline 2017; MP4002 trial Berger et al. AAAI 2016; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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