I too suffer from a strong dawn phenomenon. I have fasted & fasted to get my basals right during the morning & have found that my needs jump drastically then fall away very quickly too.
It's easiest to explain in figures. I am pretty sensitive to insulin & only have a total basal requirement of 14.5u/24hrs.
ebony321 said:
It took me a good few weeks to programme mine.. what i found was that my DP started before i actually woke up!! my basal is flat lined until 4am in the morning, then my basal rises slowly until 6am, sharply until 9am then slowly back down until 11am. then i have another flat line basal until tea time where it drops a little.
Pheeew
Ebony & I are very similar. My BG also starts to rise at around 04:00, significantly after I get up, very fast when I leave the house, then my basal needs drop away again to late morning where they settle at roughly the same rate until late afternoon when they dip a bit more.
I get up during the week at 06:00. So knowing how long it take for the insulin to get to peak activity in me (2 to 3 hours as I have a fairly poor absorption rate), I make the adjustments 2 hours before I want them to be working.
Before bed & during the early hours of the night I have only 0.4 or 0.5u/hr. This rises from 02:00 (affecting 04:00 onwards) to 0.6, 0.7 then at 04:00 jumps to 1.0. This increase is therefore working as I'm getting up and ready for work. From 07:00 to 08:00 (when I'm leaving the house & travelling on the train therefore my activity level & alertness state increase) my BG used to rise significantly, so at 05:00 my basal jumps again to 1.4. As I settle into my day, the need drops away & I drop back at 06:00 (covering 08:00-09:00) to 1.2. then 1.0, 0.9, 0.7, 0.6, 0.5 right down to 0.3 late in the afternoon.
My range therefore is from 0.3 to 1.4. I'm not sure how this compares to you, but what I'm trying to say is whatever your basic requirements (my most common basal is 0.4 or 0.5) with a strong DP, expect to need a significant amount more to counteract it.
Unfortunately, plugging away at fasting for a few hours at a time then increasing your basal (remembering to increase the rate 1, 2 or 3 hours before you want it to act depending on your absorption rate) to see how you react is the only sure way of getting it right.
I hate fasting and after having a blip in my Hba1c recently have had to start from scratch again, so I know what a pain it is. However, keep careful records (I'm a bit obsessive with this and make spreadsheets of my fasts so that I can easily compare the difference that each change makes) and hopefully you'll see the impact that each 0.1 change makes.
I have a fairly old pump which has a minimum increment of 0.1, but you probably have one with smaller incremental possibilities.
I now know that each 0.1 increase/decrease seems to reduce/increase my BG by about 1%. I found that I was having roughly the right amount of insulin over the morning, but not enough to counteract the DP & too much later on so it looked like I was spot on if I tested before breakfast & before lunch, but testing every hour during a fast showed me rising from 5.0 to 11.5 over 2 or 3 hours then dropping back again to 5.0 7 or 8 hours later.
I also test every hour when fasting, more than the DSNs recommend, but more helpful for me even if my fingers do end up like pin cushions.
I also wouldn't be too concerned about your BG rising during fasting to low double figures, a day or two of slightly high BGs is not going to affect your long term health. If you go from 5 to 12 between 6am & 10am, stop there, make a slight adjustment & try again. I fasted this Tuesday, all day, missing both breakfast & lunch. It showed me that I still have a little way to go to get it right, but I'm nearly there, I started with a BG of 6.6, dropped by 1.5% during the first hour, (so I've probably over-increased the basal around 04:00), then settled around 5.3-5.8 through the morning. I was elated that I'd finally got it right, until I suddenly went hypo at 15:00!! So back to tweaking again and dropping 0.1 in a couple of places and time to fast again next week.
Don't forget, you're not alone if you hate fasting, get grumpy with people & are generally unpleasant to be around when you're doing it! Drink lots of water & black coffee/tea it helps reduce the hunger pangs.
I also have much less DP at weekends when I sleep in until at least 08:00, so I have to have a completely different morning basal profile for days off.
Also, if you exercise irregularly (less than once every other day), don't try to fast for 2 days after exercise as your liver will be replenishing its glycogen supplies for up to 48 hours, you'll be needing slightly less insulin overall during that time and the results will be skewed because of that.
Good luck.