Child and adolescent nortriptyline single dose pharmacokinetic parameters: final report

Area of Science:

• Pharmacology
• Pediatric Medicine
• Clinical Pharmacy

Background:

• Nortriptyline is a tricyclic antidepressant used in pediatric populations.
• Understanding its pharmacokinetic profile in children and adolescents is crucial for safe and effective dosing.

Purpose of the Study:

• To determine single-dose pharmacokinetic parameters of nortriptyline in children and adolescents aged 5 to 16 years.
• To compare these parameters between younger children (5-12 years) and older adolescents (13-16 years).

Main Methods:

• A study involving 64 children and adolescents (aged 5-16) who received a single dose of nortriptyline.
• Pharmacokinetic data were analyzed separately for two age groups: 5- to 12-year-olds and 13- to 16-year-olds.

Main Results:

• Nortriptyline elimination rate and metabolism variability were similar between pediatric and adult groups.
• Children aged 5-12 years exhibited a significantly shorter mean half-life (20.8 hours) and greater mean oral clearance compared to adolescents aged 13-16 years (31.1 hours).
• The mean half-life ranged from 11.2 to 42.5 hours in younger children and 14.2 to 89.4 hours in older adolescents.

Conclusions:

• The pharmacokinetic profile of nortriptyline in children and adolescents is comparable to adults, characterized by linear elimination and wide metabolic variability.
• Age-dependent differences in half-life and oral clearance exist between younger children and older adolescents.
• A twice-daily dosage regimen for nortriptyline is recommended for the entire 5- to 16-year-old age group due to the observed range of half-lives.