Home > Medical Reference > Encyclopedia (English)

Please install flash player to see this video.

Hospital Virtual Tour

Related Content

Pronunciation:

(feks oh FEN a deen)

U.S. Brand Names:

Allegra®

Synonyms:

Fexofenadine Hydrochloride

Generic Available:

Canadian Brand Names:

Allegra®

Use:

Relief of symptoms associated with seasonal allergic rhinitis; treatment of chronic idiopathic urticaria

Pregnancy Risk Factor:

Pregnancy Implications:

Decreased fetal weight gain and survival were observed in animal studies. There are no adequate and well-controlled studies in pregnant women; use during pregnancy only if potential benefit to mother outweighs possible risk to fetus.

Lactation:

Excretion in breast milk unknown/use caution (AAP rates "compatible")

Contraindications:

Hypersensitivity to fexofenadine or any component of the formulation

Warnings/Precautions:

Safety and effectiveness in children <6 years of age have not been established.

Adverse Reactions:

>10%: Central nervous system: Headache (7% to 11%)

1% to 10%:

Central nervous system: Fever (2%), dizziness (2%), pain (2%), drowsiness (1% to 2%), fatigue (1%)

Endocrine & metabolic: Dysmenorrhea (2%)

Gastrointestinal: Nausea (2%), dyspepsia (1%)

Neuromuscular & skeletal: Back pain (2% to 3%)

Otic: Otitis media (2%)

Respiratory: Cough (4%), upper respiratory tract infection (3% to 4%), sinusitis (2%)

Miscellaneous: Viral infection (3%)

<1%, postmarketing, and/or case reports: Hypersensitivity reactions (anaphylaxis, angioedema, dyspnea, flushing, pruritus, rash, urticaria); insomnia, nervousness, sleep disorders, paroniria (terrifying dreams)

Overdosage/Toxicology:

Limited information from overdose describes dizziness, drowsiness, and dry mouth. Not effectively removed by hemodialysis. Doses up to 690 mg twice daily were administered for 1 month without significant adverse effects. Treatment is supportive.

Drug Interactions:

Substrate of CYP3A4 (minor); Inhibits CYP2D6 (weak)

Antacids (containing aluminum or magnesium): AUC of fexofenadine was decreased by 41% and Cmax by 43% with concomitant administration; separate administration is recommended.

Erythromycin: Levels of fexofenadine are increased (82% higher); not associated with increased adverse effects and no difference in QTc intervals.

Ketoconazole: Levels of fexofenadine are increased (135% higher); not associated with increased adverse effects and no difference in QTc intervals.

Ethanol/Nutrition/Herb Interactions:

Ethanol: Avoid ethanol (although limited with fexofenadine, may increase risk of sedation).

Food: Fruit juice (apple, grapefruit, orange, pineapple) may decrease bioavailability of fexofenadine by ~36%.

Herb/Nutraceutical: St John's wort may decrease fexofenadine levels.

Stability:

Store at controlled room temperature of 20°C to 25°C (68°F to 77°F). Protect from excessive moisture.

Mechanism of Action:

Fexofenadine is an active metabolite of terfenadine and like terfenadine it competes with histamine for H1-receptor sites on effector cells in the gastrointestinal tract, blood vessels and respiratory tract; it appears that fexofenadine does not cross the blood brain barrier to any appreciable degree, resulting in a reduced potential for sedation

Pharmacodynamics/Kinetics:

Onset of action: 60 minutes

Duration: Antihistaminic effect: 12 hours

Protein binding: 60% to 70%, primarily albumin and alpha1-acid glycoprotein

Metabolism: ~5% mostly by gut flora; 0.5% to 1.5% by CYP

Half-life elimination: 14.4 hours

Time to peak, serum: ~2.6 hours

Excretion: Feces (~80%) and urine (~11%) as unchanged drug

Dosage:

Oral:

Children 6-11 years: 30 mg twice daily

Children 12 years and Adults:

Seasonal allergic rhinitis: 60 mg twice daily or 180 mg once daily

Chronic idiopathic urticaria: 60 mg twice daily

Dosing adjustment in renal impairment: Clcr<80 mL/minute:

Children 6-11 years: Initial: 30 mg once daily

Children 12 years and Adults: Initial: 60 mg once daily

Administration:

Administer with water.

Monitoring Parameters:

Relief of symptoms

Patient Education:

Take as directed; do not exceed recommended dose. Store at room temperature in a dry place. If taking antacids, separate administration of antacid and this medication. Avoid use of other depressants, alcohol, or sleep-inducing medications unless approved by prescriber. You may experience mild drowsiness or dizziness (use caution when driving or engaging in tasks requiring alertness until response to drug is known); or nausea (small, frequent meals, frequent mouth care, chewing gum, or sucking hard candy may help). Report persistent sedation or drowsiness, menstrual irregularities, or lack of improvement or worsening or condition. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Consult prescriber if breast-feeding.

Dental Health: Effects on Dental Treatment:

No significant effects or complications reported

Dental Health: Vasoconstrictor/Local Anesthetic Precautions:

No information available to require special precautions

Mental Health: Effects on Mental Status:

May cause drowsiness or dizziness

Mental Health: Effects on Psychiatric Treatment:

None reported

Dosage Forms:

Tablet, as hydrochloride: 30 mg, 60 mg, 180 mg

International Brand Names:

Alerfedine® (AR); Alernex® (IN); Alexia® (CL); Allegra® (AR, BR, CA, CL, CO, CR, DO, GT, HN, IN, MX, PA, SV); Fexoalergic® (CR, GT, PA); Fexofen® (TR); Kalicet® (IT); Telfast® (AT, AU, BE, CH, DE, DK, ES, FI, FR, GB, HR, HU, ID, IE, IL, IT, NL, NO, NZ, PL, PT, RO, RU, SE, SG, TH, TR, YU, ZA)

References

"American Academy of Pediatrics Committee on Drugs. The Transfer of Drugs and Other Chemicals Into Human Milk,"Pediatrics, 2001, 108(3):776-89.

Day JH, et al, "Onset of Action, Efficacy and Safety of a Single Dose of 60 mg and 120 mg Fexofenadine HCl for Ragweed Allergy Using Controlled Antigen Exposure in an Environmental Exposure Unit,"J Allergy Clin Immunol, 1996, 97(1 Pt 3):1007.

"Fexofenadine,"Med Lett Drugs Ther, 1996, 38(986):95-6.

Simons FE, Bergman JN, Watson WT, et al, "The Clinical Pharmacology of Fexofenadine in Children,"J Allergy Clin Immunol, 1996, 98(6 Pt 1):1062-4.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.