Use of amlodipine oral solution for the treatment of hypertension in children

Background Amlodipine is a widely used antihypertensive agent for the treatment of paediatric hypertension, but the commercially available tablets are not suitable to treat young patients, who need lower, flexible dosages and a liquid formulation. Objective To determine the pharmacokinetic properties of amlodipine and the acceptability of a standardised, extemporaneous oral solution. Method A newly developed liquid formulation of amlodipine was administered to hypertensive children between the age of 6 months and 11 years. Using a limited sampling strategy, population PK analysis was performed using nonlinear mixed effects modelling. Results Nine children, with a median age of 2.9 years (IQR 1.8–8.4), receiving stable amlodipine therapy in a median dose of 0.15 mg kg⁻¹ day⁻¹ (IQR 0.11–0.18), were switched to study medication. The population pharmacokinetic model was able to accurately predict the clearance of amlodipine in the study population. Based on the final model, clearance was reduced by 31.2% (RSE: 10%) in females. Patient reported outcomes on taste from a five-point hedonic scale were available for five patients, who scored the taste from positive to slightly negative. Conclusion The results from the PK study and the acceptability assessment show that the amlodipine oral solution presented in this study offers an appropriate treatment option for young children.