The pharmacokinetics of diphemanil methylsulphate was evaluated after
oral administration of a single 3 mg . kg-1 dose to 5 infants being tr
eated for symptomatic bradycardia. The mean pharmacokinetic parameters
of oral diphemanil methylsulphate in infants were similar to those in
adults. The mean half-life was 8.6 h. This would allow administration
three times a day in infants instead of four to six times a day, as c
urrently prescribed. The mean residence time decreases significantly w
ith age (Spearman's r'= -1), and there is a trend for the half-life to
decrease with age (r'= -0.9; NS), suggesting an influence of maturati
on on its elimination.