The effectiveness of florinef in the body is about 26 hrs give or take 4 hrs which is close enough to 24 hrs. Some people metabolize drugs faster than others and therefore fall on the low end of that time frame, others fall on the high end. Florinef's effectiveness and metabolism in babies is not really known. Babies in general metabolize things much quicker so sometimes endos divide up their dose into two just to give a bigger effective dose. Since people are more active during the day and eat and drink more and produce more urine some endos prefer to give florinef in the morning. But whatever you do as long as the renin levels are fine and the blood pressure is fine then florinef is working for you. It is when those are not fine that the endos start to play around with the timing.