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Second-generation (non-sedating) antihistamine — H1 antagonist

Loratadine 10mg Tablets

Brand names: Clarityn, Boots Allergy Relief

Loratadine tablets are a non-sedating, second-generation oral antihistamine used for symptomatic relief of allergic rhinitis and other allergic conditions managed within ENT practice.

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

Loratadine is a selective peripheral histamine H1-receptor antagonist; by blocking H1 receptors it reduces the sneezing, rhinorrhoea, nasal itch and watery eyes driven by histamine release.

Prescribing in practice

  • Although classed as non-sedating, drowsiness can still occur in some individuals, so advise caution with driving or skilled tasks until the response is known.
  • Dose reduction or alternate-day dosing is advised in significant hepatic impairment, where clearance of loratadine and its active metabolite is reduced.
  • It is taken once daily and offers no benefit over and may interact additively with other sedating antihistamines if combined.

Monitoring

Routine laboratory monitoring is not required; review symptom control and tolerability, and reassess any unexpected sedation.

Counselling the patient

  • Take one tablet once daily, with or without food.
  • Most people are not made drowsy, but stop driving if you do feel sleepy.
  • It controls symptoms while you take it rather than curing the underlying allergy.

Evidence & guidelines

Loratadine is a well-established first-line non-sedating antihistamine for allergic rhinitis, supported by long clinical use and reflected in NICE guidance and the SPC.

Reference: ARIA Guidelines; BSACI Allergic Rhinitis; 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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