NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated July 13, 2026

Loratadine

Prescription ·Exploratory record · not publication-reviewed ·Updated July 13, 2026

A second-generation antihistamine with minimal sedative effects, used for the symptomatic relief of seasonal and perennial allergic rhinitis and chronic idiopathic urticaria. One of the least sedating oral antihistamines due to very limited CNS penetration. Available over-the-counter and widely used for its favorable tolerability profile. Active metabolite desloratadine (Clarinex) is also marketed separately.

Evidence tier
Strong
Indexed sources
11 1998–2025
Interactions
0
Category
Prescription
Read the sources → Compare profiles
Publication status

Exploratory record, not a reviewed medical publication.

See the editorial and medical-review policies for the publication gate.

This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.

In short

What the research says.

A quick, data-only summary. The full evidence, dosing, and sources are below.

A second-generation antihistamine with minimal sedative effects, used for the symptomatic relief of seasonal and perennial allergic rhinitis and chronic idiopathic urticaria. NutriStack rates the supporting evidence as strong. Common adult dosing is Adults and children >=6 years: 10 mg once daily; children 2-5 years: 5 mg once daily (as prescribed by your physician), though a prescriber sets the actual dose. This profile indexes 11 sources.

What it's good for
  • Relieves allergic rhinitis symptoms (sneezing, itching, rhinorrhea)1,2
  • Treats chronic idiopathic urticaria5
  • Minimal sedation (less than cetirizine)4
  • Once-daily dosing6
  • Available over-the-counter
What to watch for
  • Headache
  • Drowsiness (uncommon, near placebo rates)
  • Fatigue
  • Known hypersensitivity to loratadine or desloratadine1,2
  • Severe hepatic impairment (dose adjustment: 10 mg every other day)

The bottom line

Evidence rating strong. Most-documented uses: relieves allergic rhinitis symptoms (sneezing, itching, rhinorrhea), treats chronic idiopathic urticaria, minimal sedation (less than cetirizine). 11 sources indexed (1998–2025), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

A long-acting selective peripheral H1 receptor antagonist. Competitively blocks H1 histamine receptors on target cells, preventing the vasodilatory, permeability-enhancing, and pruritic effects of histamine released during allergic reactions. Also inhibits histamine release from mast cells. At therapeutic doses, loratadine does not significantly cross the blood-brain barrier (P-glycoprotein substrate), resulting in minimal CNS sedation and no significant anticholinergic effects.

Class
Second-Generation Antihistamine
Dosing

Dosing & protocol.

Common range
Adults and children >=6 years: 10 mg once daily; children 2-5 years: 5 mg once daily (as prescribed by your physician)
Recommended form
Oral tablets, orally disintegrating tablets (Reditabs), or liquid syrup

Rapidly absorbed; food delays absorption by approximately 1 hour but does not affect total bioavailability. Can be taken with or without food. Extensively metabolized by CYP3A4 and CYP2D6 to active metabolite desloratadine.

Safety

Full safety detail.

Side effects

  • Headache
  • Drowsiness (uncommon, near placebo rates)
  • Fatigue
  • Dry mouth
  • Nervousness (children)

Contraindications

  • Known hypersensitivity to loratadine or desloratadine1,2
  • Severe hepatic impairment (dose adjustment: 10 mg every other day)
  • Severe renal impairment (GFR <30 mL/min, dose adjustment: 10 mg every other day)
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Meta-analyses & systematic reviews

3

Randomized controlled trials

3

Reviews & position papers

1

Reference material

4
FAQ

Common questions.

Quick answers about Loratadine, drawn from the data on this page.

What is Loratadine?

A second-generation antihistamine with minimal sedative effects, used for the symptomatic relief of seasonal and perennial allergic rhinitis and chronic idiopathic urticaria. One of the least sedating oral antihistamines due to very limited CNS penetration. Available over-the-counter and widely used for its favorable tolerability profile. Active metabolite desloratadine (Clarinex) is also marketed separately.

What is Loratadine used for?

Commonly cited benefits of Loratadine include: Relieves allergic rhinitis symptoms (sneezing, itching, rhinorrhea); Treats chronic idiopathic urticaria; Minimal sedation (less than cetirizine); Once-daily dosing; Available over-the-counter. NutriStack rates the overall evidence as strong.

What is a typical dose of Loratadine?

A typical adult dose of Loratadine is Adults and children >=6 years: 10 mg once daily; children 2-5 years: 5 mg once daily (as prescribed by your physician). The commonly recommended form is Oral tablets, orally disintegrating tablets (Reditabs), or liquid syrup. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Loratadine?

Reported side effects include headache, drowsiness (uncommon, near placebo rates), fatigue, dry mouth, nervousness (children). This is educational information; check with a healthcare professional before use.

How strong is the evidence for Loratadine?

NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.

Use this with your stack

Loratadine in NutriStack.

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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.