Adjusting basal rates

I am a little confused.John Walsh’s book says to change the basal rate at least 4-8hours before the low or high occurred.But I also read that it should be 2 hours before the low or high because it takes the insulin 1 hour to peak.That would make more sense to me from what I have observed.What is the proper time?

I use about 2 hours. 8 hours in my opinion is a very long time. Basal insulin rates are trial-and-error so be careful. I try not to makes changes greater than 20% at one time. I am re-doing my day rate right now and my fingers are sore! =) Good luck Dee

I thought that suggestion was weird when I read it, too. I have always heard 2 hours before from CDEs.

I use between 60 and 90 min. If I go a full 2 hours I have a big swing.

Insulin seems to take about two hours for me to have an effect, whether in a basal change or in a bolus, and it also can depend on the time of day – I need two hours for a change to take effect in the morning, but only about 90 days in the late afternoon.