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Mast Cell Stabiliser — Allergic Rhinitis

Sodium Cromoglicate Nasal Spray

Brand names: Rynacrom, Nasocrom

Sodium cromoglicate nasal spray is a topical mast-cell stabiliser used for the prevention and treatment of allergic rhinitis, including seasonal (hay fever) and perennial symptoms.

Dosing — no UK product information found

We found no UK product information (SmPC) for this medicine or presentation on the eMC or MHRA Products (checked October 2026). It may be unlicensed in the UK, imported, a medical device, or no longer marketed. ClinCalc Pro shows only doses it can trace to official product information, so none is shown — follow your specialist service or local guideline.

Clinical monograph

How it works

It stabilises sensitised mast cells within the nasal mucosa, inhibiting degranulation and the release of histamine and other inflammatory mediators that drive the allergic response.

Prescribing in practice

  • It is prophylactic and works best when started before and used regularly throughout allergen exposure, requiring several-times-daily dosing rather than as-needed use.
  • Onset of benefit is gradual, so set expectations that full effect may take some days of consistent use.
  • It is generally well tolerated with minimal systemic absorption, but transient local nasal irritation or sneezing can occur after instillation.

Monitoring

No specific monitoring is needed; review symptom control and adherence, and reconsider the regimen if response is inadequate.

Counselling the patient

  • Use every day throughout the allergy season, not just when symptoms flare.
  • Start before expected pollen exposure where possible for best results.
  • Mild nasal stinging or sneezing just after spraying is common and usually settles.

Evidence & guidelines

Topical cromoglicate is a recognised option for allergic rhinitis, particularly where regular prophylaxis is preferred or other agents are unsuitable.

Reference: BSACI Rhinitis Guidelines 2017; RCOG (2022) Pharmacology in pregnancy; 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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