In a group of 30 digitalized children, we compared the digoxin levels in capillary and venous plasma samples, both of which were obtained simultaneously from each child. We statistically concluded that the venous plasma samples could surely be replaced by capillary plasma samples for measurements of plasma digoxin levels without any significant difference. Additionally, we showed that storing the capillary plasma samples at room temperature for 3 days did not lead to any significant change in digoxin levels. This is an important point for the hospitals and practitioners who do not have their own possibilities for digoxin determination.