A Histamine Pharmacodynamic Biomarker to Guide Treatment in Pediatric Asthma (HAS3)

At the end of the HILD assessment participants will be randomized to Levocetirizine Dihydrochloride or placebo. Children will be randomized by an investigational pharmacist to add-on either Levocetirizine dihydrochloride/ Xyzal® (UCB, Inc.) immediate release oral solution 2.5mg/5ml (2.5mg in children 6-11 years of age; 5mg in children \>11 years per recommended doses) or placebo to their current asthma regimen.

Placebo