The pharmacokinetics and pharmacodynamics of terfenadine in children.

Abstract

The pharmacokinetics and pharmacodynamics of terfenadine were studied in 13 children with allergic rhinitis, mean age 7.45 +/- 0.54 SEM years. Serum concentrations of the active carboxylic acid metabolite of terfenadine (terfenadine metabolite I) were measured before and hourly for 8 hours after administration of a single dose of terfenadine suspension. The mean maximum serum concentration of terfenadine metabolite I, 242 +/- 28 ng/ml, occurred at 2.3 +/- 0.2 hours; the mean serum half-life value was 2.0 +/- 0.1 hours. Wheals and flares after epicutaneous tests with histamine phosphate, 1.0 mg/ml and 0.2 mg/ml, were significantly suppressed from 1 to 8 hours after the terfenadine dose compared to predose values. Maximum wheal suppression occurred at from 3 to 6 hours. Itching was completely suppressed for 8 hours. No serious adverse effects occurred. Terfenadine in children appears to be well absorbed, and its carboxylic acid metabolite has a short serum elimination half-life. The duration of its suppressive effect on the histamine-induced wheal and flare greatly exceeds that expected from consideration of serum terfenadine metabolite I concentrations.

• Authors: F E Simons, W T Watson, K J Simons
• Journal: The Journal of allergy and clinical immunology (J Allergy Clin Immunol) Vol. 80 Issue 6 Pg. 884-90 (Dec 1987) ISSN: 0091-6749 [Print] United States
• PMID: 2891738 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Benzhydryl Compounds
• Histamine H1 Antagonists
• Terfenadine

Topics

• Benzhydryl Compounds (adverse effects, pharmacokinetics, pharmacology)
• Child
• Child, Preschool
• Female
• Half-Life
• Histamine H1 Antagonists (adverse effects, pharmacokinetics, pharmacology)
• Humans
• Male
• Rhinitis, Allergic, Perennial (blood, immunology)
• Skin Tests
• Terfenadine