Overview
| Generic Names: | Carboxyterfenadine; Fexofenadine hydrochloride; Fexofendine; Terfenadine acid metabolite; Terfenadine carboxylate; Terfenadine-COOH |
|---|---|
| Trade Names: | Allegra |
| Brand Mixtures: | Allegra-D (Fexofenadine hydrochloride + Pseudoephedrine hydrochloride) |
| PharmGKB Accession Id: | PA449621 |
Description
Fexofenadine hydrochloride (Allegra) is an antihistamine drug used in the treatment of hayfever and similar allergy symptoms. It was developed as a successor of and alternative to terfenadine. Fexofenadine, like other second and third-generation antihistamines, does not readily pass through the blood-brain barrier, and so causes less drowsiness than first-generation histamine-receptor antagonists. (source: Drug Bank)
Indication
For management of Seasonal allergic rhinitis (source: Drug Bank)
ATC Therapeutic Category
- R06AX:Other antihistamines for systemic use
Pharmacology, Interactions, and Contraindications
Mechanism Of Action
Like other H1-blockers, Fexofenadine competes with free histamine for binding at H1-receptors in the GI tract, large blood vessels, and bronchial smooth muscle. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Fexofenadine exhibits no anticholinergic, alpha1-adrenergic or beta-adrenergic-receptor blocking effects. (source: Drug Bank)
Pharmacology
Fexofenadine is a second-generation, long lasting H1-receptor antagonist (antihistamine) which has a selective and peripheral H1-antagonist action. Histamine is a chemical that causes many of the signs that are part of allergic reactions, for example, swelling of tissues. Histamine is released from histamine-storing cells (mast cells) and attaches to other cells that have receptors for histamine. The attachment of the histamine to the receptors causes the cell to be "activated," releasing other chemicals which produce the effects that we associate with allergy. Fexofenadine blocks one type of receptor for histamine (the H1 receptor) and thus prevents activation of cells by histamine. Unlike most other antihistamines, Fexofenadine does not enter the brain from the blood and, therefore, does not cause drowsiness. Fexofenadine lacks the cardiotoxic potential, since it does not block the potassium channel involved in repolarization of cardiac cells. (source: Drug Bank)
Food Interactions
Grapefruit and grapefruit juice should be avoided throughout treatment as grapefruit can significantly decrease serum levels of this product.
Take without regard to meals.
(source:
Drug Bank)
Absorption, Distribution, Metabolism, Elimination & Toxicity
Biotransformation
Approximately 5% of the total dose is metabolized, by cytochrome P450 3A4 and by intestinal microflora. (source: Drug Bank)
Protein Binding
60%-70% (source: Drug Bank)
Absorption
33% (source: Drug Bank)
Toxicity
Side effects include dizziness, drowsiness, and dry mouth. (source: Drug Bank)
Isomeric SMILES Code:
CC(C)(C1=CC=C(C=C1)[C@@H](CCCN2CCC(CC2)C(C3=CC=CC=C3)(C4=CC=CC=C4)O)O)C(=O)O (source: Drug Bank)
In-Depth Annotations (
)
-
rs1045642
at chr7:86976581
in
ABCB1
Risk or phenotype-associated allele: TT genotype. Phenotype: Increased cellular rhodamine levels in leukocytes isolated from subjects (p < 0.05), but no association with fexofenadine plasma levels in the subjects. Study size: 20. Study population/ethnicity: Caucasian volunteers from Germany. Significance metric(s): p < 0.05 Type of association: GN; PK; FA.- Variant Name:
- ABCB1:3435T>C, Ile1145Ile
- Related Drugs:
- fexofenadine, rhodamine 123
- Evidence:
-
PMID:11994059
http://www.pharmgkb.org/.../variant.jsp#ImportantVariantInformationforABCB1-3435
Curated Annotations (
)
-
rs1045642
at chr7:86976581
in
ABCB1
3435TT homozygotes showed statistically different fenofexadine area under the concentration curve (AUC) values for 0-4 hours (p = 0.036) than CC homozygotes.- Variant Name:
- ABCB1:3435C>T, mRNA 3853C>T, Ile1145Ile
- Related Drugs:
- fexofenadine
- Evidence:
-
PMID:11503014
-
rs2032582
at chr7:86998554
in
ABCB1
893Ser-expressing (ABCB1:2677G>T (Ala893Ser)) cells showed 47% lower intracellular digoxin concentration (p < 0.002) than Ala893-expressing cells; and 893Ser/Ser homozygotes showed statistically different fenofexadine area under the concentration curve (AUC) values for 0-4 hours (p = 0.054) than 893Ala/Ala homozygotes.- Variant Name:
- ABCB1:2677G>T/A, mRNA 3095G>T/A, Ala893Ser/Thr
- Related Drugs:
- digoxin, fexofenadine
- Evidence:
-
PMID:11503014
The following genes are in curated knowledge about this drug.
| Gene | Relationship | Evidence | |
|---|---|---|---|
|
ABCB1 |
|
Publications, Variants |
|
|
CYP3A4 |
|
Publications |
|
SLCO1A2 |
|
Publications |
|
|
SLCO1B1 |
|
Publications |
|
|
SLCO1B3 |
|
Publications |
|
|
SLCO2B1 |
|
Publications |
A list of non-curated publications that mention this drug along with other genes is available.
Drug Targets
| Gene | Description | |
|---|---|---|
| HRH1 |
|
(source: Drug Bank) |
A list of non-curated publications that mention this drug along with other drugs is available.
Drug Interactions
| Drug | Description | |
|---|---|---|
| cisapride |
|
Increased risk of cardiotoxicity and arrhythmias (source: Drug Bank) |
Non-Curated Information
A list of non-curated publications that mention this drug along with other diseases is available.
LinkOuts
Common Searches
Search PubMed
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Search CTD
Non-Curated Publications
A list of non-curated publications that mention this drug is available.