Effect of administration route on the pharmacokinetics of cobalamin in elderly

Abstract

ntroduction.– The standard treatment for cobalamin deficiency s supplementation by intramuscular injection. These injections, owever, are painful and inconvenient. It is thought that cobalmin can also be administered intranasally. Previous studies do ot provide insight in the pharmacokinetics in deficient elderly or in comparison with cobalamin injection. Here we aimed at uantifying the pharmacokinetics of intranasal and intramuscular dministered cobalamin in elderly cobalamin deficient patients. ethods.– Ten subjects were recruited and randomly divided nto two groups. A single dose of 1mg cobalamin was adminisered either by way of intranasal spray or intramuscular injection. nclusion criteria were written informed consent >65 years and obalamin serum concentration<200pmol/l. Total cobalamin erum concentrations were determined at ten different time interals. The average Tmax, Cmax, and AUC0–48 hours per administration oute were statistically compared with ANOVA. esults.– After intranasal cobalamin administration, the average max was 42minutes versus 342minutes for intramuscular adminstration. The average Cmax was 1040pmol/l versus 38486pmol/l, espectively. Due to the significant differences in Tmax andCmax, the UC0-48 hours also differed significantly between these two adminstration routes. iscussion and conclusion.– The pharmacokinetics of cobalamin fter intranasal and intramuscular administration differ signifiantly. Oral administration has been shown to be effective in the reatment of cobalamin deficiency. A Cmax comparable to the Cmax ound in this study after intranasal administration is reached after single oral dose of 1mg cobalamin. Therefore, further research n the safety, pharmacokinetics and efficacy of repeated intranasal obalamin administration is warranted. isclosure.– No significant relationships.