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Published on: February 11, 2019
Comparison of CNS adverse effects between astemizole and chlorpheniramine in children: a randomized, double-blind
A Shanon1, W Feldman, L Leikin
1Department of Pediatrics, Children's Hospital of Eastern Ontario, Ottawa, Canada.
Insights
This study found that common antihistamines chlorpheniramine and astemizole had no negative impact on children's cognitive performance or physical side effects. Both medications were well-tolerated, showing no significant adverse effects in children with allergic rhinitis.
Area of Science:
- Pediatric Allergy and Immunology
- Clinical Pharmacology
- Neuroscience
Background:
- Antihistamines are widely used to manage allergic rhinitis in children.
- Concerns exist regarding potential central nervous system (CNS) side effects of older antihistamines like chlorpheniramine.
- Newer antihistamines, such as astemizole, were developed with the aim of reduced CNS effects.
Purpose of the Study:
- To evaluate and compare the central nervous system (CNS) side effects of chlorpheniramine and astemizole in pediatric patients.
- To assess the impact of these antihistamines on cognitive functions including attention, memory, and motor skills.
Main Methods:
- A prospective, randomized, double-blind, cross-over study design was employed.
- 92 children aged 8-16 with allergic rhinitis participated, receiving either chlorpheniramine or astemizole over 13 weeks with a wash-out period.
- Cognitive performance was assessed using tests for attention, memory, and motor coordination, alongside monitoring for physical side effects.
Main Results:
- No significant differences in adverse effects were observed between chlorpheniramine and astemizole, or compared to baseline.
- Cognitive assessments, including the visual retention test and continuous performance test, showed no significant drug effects.
- A slight improvement in the visual aural digit span test was noted with astemizole treatment.
Conclusions:
- The antihistamines chlorpheniramine and astemizole demonstrated no adverse effects on the cognitive performance of children.
- Both medications were found to be safe and well-tolerated in the pediatric population studied.
- These findings support the use of these antihistamines in children with allergic rhinitis without significant concern for CNS impairment.
Objective:
To assess the central nervous system side effects of chlorpheniramine and astemizole in children.
Design:
Prospective, randomized, double-blind cross-over study.
Setting:
Children were recruited from the out-patient allergy clinic and from respondents to an advertisement in a local newspaper. The study was conducted in the outpatient clinics of the ambulatory care services of the Children's Hospital of Eastern Ontario.
Patients, Participants:
Children 8-16 years of age, with isolated allergic rhinitis or hay fever, were eligible for the study. We excluded children with: (1) chronic conditions (specifically asthma, atopic dermatitis, learning disabilities, or current treatment with oral corticosteroid medication); (2) known allergy to the study medications; (3) recent use of any antihistamine medication. One hundred and three children entered the study and 92 completed it.
Interventions:
Children were stratified by age and randomly allocated to treatment with one of the two medication sequences. Over a period of 13 weeks both groups had 1 week of baseline studies, 3 weeks of one study medication, either chlorpheniramine or astemizole, a 6-week wash-out period and then 3 weeks of the other study medication for a second treatment period.
Main Outcome Measures:
Attention span (continuous performance test), short-term auditory and visual memory (visual aural digit span test), visual memory for geometric shapes (Benton visual retention test), motor coordination and visual-motor integration (grooved pegboard test), tapping speed and fine motor coordination (finger tapping test), physical side effects (such as sleepiness and dizziness), and compliance.
Results:
One hundred and three patients were enrolled in the study, 92 (89%) completed the study. There were no significant drug effects on the visual retention test and the continuous performance test. On the visual aural digit span test, patients treated with astemizole scored higher than at baseline. There were no clinical or statistical differences in adverse effects between the two medications or between each medication and baseline.
Conclusions:
The two antihistamines studied had no adverse effects on the performance of children.
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