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

Fexofenadine

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

A second-generation antihistamine that is the active carboxylate metabolite of terfenadine. Provides effective relief of allergic rhinitis symptoms and chronic idiopathic urticaria with virtually no sedation or cognitive impairment at recommended doses, considered the least sedating of the second-generation antihistamines. Does not cause QT prolongation (unlike its parent compound terfenadine). Available over-the-counter.

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 that is the active carboxylate metabolite of terfenadine. NutriStack rates the supporting evidence as strong. Common adult dosing is Adults and children >=12 years: 60 mg BID or 180 mg once daily; children 2-11 years: 30 mg BID (as prescribed by your physician), though a prescriber sets the actual dose. This profile indexes 11 sources.

What it's good for
  • Treats seasonal and perennial allergic rhinitis5,6
  • Treats chronic idiopathic urticaria6,10
  • Truly non-sedating at recommended doses
  • No QT prolongation risk
  • No cognitive or psychomotor impairment
What to watch for
  • Headache
  • Drowsiness (near placebo rates)
  • Nausea
  • Known hypersensitivity to fexofenadine or terfenadine1,2
  • Severe renal impairment (dose reduction recommended)

The bottom line

Evidence rating strong. Most-documented uses: treats seasonal and perennial allergic rhinitis, treats chronic idiopathic urticaria, truly non-sedating at recommended doses. 11 sources indexed (2000–2024), with 0 interaction records on file.

The science

How it works, mechanistically.

Core mechanism

Selectively antagonizes peripheral H1 histamine receptors with high binding affinity and very slow receptor dissociation. Inhibits histamine-induced vasodilation, increased vascular permeability, pruritus, and smooth muscle contraction. Does not cross the blood-brain barrier at therapeutic doses (substrate of P-glycoprotein efflux pump and organic anion transporting polypeptide [OATP]). No significant anticholinergic, anti-alpha-adrenergic, or anti-serotonergic activity. Does not affect cardiac potassium channels (no QTc effect).

Class
Second-Generation Antihistamine
Dosing

Dosing & protocol.

Common range
Adults and children >=12 years: 60 mg BID or 180 mg once daily; children 2-11 years: 30 mg BID (as prescribed by your physician)
Recommended form
Oral tablets, orally disintegrating tablets, or oral suspension

Bioavailability approximately 33%. Do NOT take with fruit juices (apple, orange, grapefruit), they inhibit OATP1A2 organic anion transporting polypeptide, reducing absorption by up to 36%. Take with water. Food has no clinically significant effect on absorption. Avoid high-fat meals which may slightly reduce absorption.

Safety

Full safety detail.

Side effects

  • Headache
  • Drowsiness (near placebo rates)
  • Nausea
  • Dysmenorrhea
  • Back pain
  • Upper respiratory symptoms

Contraindications

  • Known hypersensitivity to fexofenadine or terfenadine1,2
  • Severe renal impairment (dose reduction recommended)
  • Concomitant use with aluminum/magnesium-containing antacids (separate by 2 hours)
Sources

Sources, by evidence tier.

Numbered references. Citations throughout the page link here.

Meta-analyses & systematic reviews

4

Randomized controlled trials

2

Reviews & position papers

1
  • 7Fexofenadine: review of safety, efficacy and unmet needs in children with allergic rhinitisPMIDMeltzer EO, Rosario NA, Van Bever H et al. · Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology · 2021

    Meltzer EO, Rosario NA, Van Bever H et al.. Fexofenadine: review of safety, efficacy and unmet needs in children with allergic rhinitis. Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology. 2021

FAQ

Common questions.

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

What is Fexofenadine?

A second-generation antihistamine that is the active carboxylate metabolite of terfenadine. Provides effective relief of allergic rhinitis symptoms and chronic idiopathic urticaria with virtually no sedation or cognitive impairment at recommended doses, considered the least sedating of the second-generation antihistamines. Does not cause QT prolongation (unlike its parent compound terfenadine). Available over-the-counter.

What is Fexofenadine used for?

Commonly cited benefits of Fexofenadine include: Treats seasonal and perennial allergic rhinitis; Treats chronic idiopathic urticaria; Truly non-sedating at recommended doses; No QT prolongation risk; No cognitive or psychomotor impairment. NutriStack rates the overall evidence as strong.

What is a typical dose of Fexofenadine?

A typical adult dose of Fexofenadine is Adults and children >=12 years: 60 mg BID or 180 mg once daily; children 2-11 years: 30 mg BID (as prescribed by your physician). The commonly recommended form is Oral tablets, orally disintegrating tablets, or oral suspension. These are general ranges, not personalized advice; confirm the right dose with a clinician.

What are the side effects of Fexofenadine?

Reported side effects include headache, drowsiness (near placebo rates), nausea, dysmenorrhea, back pain, upper respiratory symptoms. This is educational information; check with a healthcare professional before use.

How strong is the evidence for Fexofenadine?

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

Fexofenadine in NutriStack.

Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.

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.