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

Prior treatment

• Previous history of adverse drug reaction to Levocetirizine (LTZ)
• Unwillingness or inability to washout of medications that affect histamine response
• Currently on or has been on Tricyclic Antidepresants in past 30 days

Other illness

• Any other chronic disease states such as history of premature lung disease, bronchiectasis, cystic fibrosis, or any chronic lung disease other than asthma.
• Chronic abnormal conditions of the liver or kidney, immunologic/hematologic, or neoplastic disease as determined by the PI (the following questions will be asked at initial screening to identify children with potential abnormal kidney function:
  • Have you ever been diagnosed with chronic kidney disease?; Have you ever had to be on dialysis or take medications for chronic kidney disease?)

Lab values

• Clinically significant abnormal safety laboratory values as determined by study physician

Age

• Age 18 years or older at the time of enrollment.

Other

• For females, positive pregnancy test (by urinary hCG) or lactation at the time of the study
• Inability or unwillingness to have blood drawn as described in the protocol schedule of events and consent, or inability or unwillingness to cooperate with study procedures.
• Active eczema at the site where histamine laser doppler probe will be place(forearm) on the day of histamine laser doppler iontophoresis
• Those whom are pregnant, prisoners, and/or wards of the state.

• A diagnosis of asthma based on physician diagnosis
• A diagnosis of uncontrolled asthma based on Asthma Control Test (ACT) score within the last 3 months or at screening
• Evidence of allergic sensitization based on allergy skin test or allergy blood test results
• Individuals who are currently being treated with asthma guideline-based therapy
• Males and females 6 through 17 years of age at time of enrollment
• Willing to provide written permission/assent to participate
• Children who self-identify as African American/black (identify both 1st degree (parents) and 2nd degree relatives (grandparents) as African American) or Caucasian/white (self-report of 1st and 2nd degree relatives as Caucasian)