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Second-generation (non-sedating) antihistamine — H1 antagonist Pregnancy: A large amount of data (>1000 exposed pregnancy outcomes) indicates no malformative or feto/neonatal toxicity, but as a precautionary measure it is preferable to avoid loratadine during pregnancy. Loratadine is excreted in breast milk, so use is not recommended in breast-feeding women (§4.6).

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.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 10 mg (one tablet)
Route: Oral
Frequency: Once daily
Adults and children over 12 years of age: 10 mg once daily (§4.2). May be taken without regard to mealtime. Paediatric (weight-banded, not per kg): children 2 to 12 years are dosed by weight — body weight more than 30 kg, 10 mg once daily; body weight 30 kg or less, the 10 mg tablet is not appropriate and other formulations are more suitable. Efficacy and safety in children under 2 years have not been established. Hepatic impairment: patients with severe liver impairment should be given a lower initial dose because of reduced loratadine clearance — an initial dose of 10 mg every other day is recommended for adults and children weighing more than 30 kg. No dose adjustment required in renal insufficiency or in the elderly. §4.4 advises stopping this medicine at least 48 hours before skin tests, since antihistamines may prevent or reduce positive dermal reactivity. Source product: 'Brown & Burk Once-A-Day Hayfever & Allergy 10 mg Tablets' SPC. US OTC labelling (cross-check only) states adults and children 6 years and over: 1 tablet daily, not more than 1 tablet in 24 hours.

Dose adjustments

Renal

No dosage adjustments are required in patients with renal insufficiency (§4.2).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance or to any of the excipients (§4.3)

Side effects

  • Somnolence (1.2% in adults/adolescents at 10 mg daily) (§4.8)
  • Headache (0.6%) (§4.8)
  • Increased appetite (0.5%) (§4.8)
  • Insomnia (0.1%) (§4.8)
  • Very rare: hypersensitivity reactions including angioedema and anaphylaxis (§4.8)
  • Very rare: tachycardia, palpitation; dizziness, convulsion; abnormal hepatic function; rash, alopecia (§4.8)

Interactions

  • Potential interaction with all known inhibitors of CYP3A4 or CYP2D6, resulting in elevated loratadine levels and possible increase in adverse events (§4.5)
  • Increased loratadine plasma concentrations reported with ketoconazole, erythromycin and cimetidine in controlled trials, but without clinically significant changes (including electrocardiographic) (§4.5)
  • Alcohol: no potentiating effect as measured by psychomotor performance studies (§4.5)

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. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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