fexofenadine (Allegra)
Jump to navigation
Jump to search
Introduction
Tradename: Allegra. (fexofenadine HCl) Empirical formula: C32H39NO4*HCl.
Indications
- seasonal allergic rhinitis in adults & children > 12 years of age
- allergic conjunctivitis
- urticaria
Dosage
Tabs: 60 mg.
Dosage adjustment in renal failure
- 60 mg QD for creatinine clearance < 80 mg/dL
Pharmacokinetics
- onset of action 3 hours[5]
- negligible (5%) metabolism
- active metabolite of terfenadine
- bioavailability[3]
- absorption dependent upon an anion transporter, organic anion transporting polypeptide (OATP)[6]
- absorption inhibited up to 70% when taken with fruit juice[6] (orange juce, grapefruit juice)
- elimination 80% in feces, 11% in urine
- 1/2life 14.4 hours
- 21 hours with creatinine clearance 40-80 mL/min
- 25 hours with creatinine clearance 10-40 mL/min
- protein binding 60-70%
- binds to albumin, alpha-1 acid glycoprotein
1/2life = 14 hours
elimination via liver
elimination via kidney
elimination by hemodialysis = -
Adverse effects
(uncommon)
- flu-like symptoms (2.5%)
- nausea (1.5%)
- dysmenorrhea (1.5%)
- drowsiness (1.3%)
- dyspepsia (1.3%)
- fatigue (1.3%)
- no prolongation of QT interval
Drug interactions
- erythromycin & ketoconazole increase fexofenadine levels, but (up to 80%) but not associated with increased incidence of adverse effects
Laboratory
More general terms
Component of
References
- ↑ Hoest Marion Roussel
- ↑ Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998, pg 34
- ↑ 3.0 3.1 Kaiser Permanente Northern California Regional Drug Formulary, 1998
- ↑ Prescriber's Letter 8(6):33 2001
- ↑ 5.0 5.1 Prescriber's Letter 15(7): 2008 Comparison of Antihistamines Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=240707&pb=PRL (subscription needed) http://www.prescribersletter.com
- ↑ 6.0 6.1 6.2 Prescriber's Letter 18(6): 2011 OATP Fruit Juice Drug Interactions Detail-Document#: http://prescribersletter.com/(5bhgn1a4ni4cyp2tvybwfh55)/pl/ArticleDD.aspx?li=1&st=1&cs=&s=PRL&pt=3&fpt=25&dd=270602&pb=PRL (subscription needed) http://www.prescribersletter.com