I am getting highs in the teens after those meals whatever timing I use, and then lows in the 4s at night.
When you say "whatever timing I use" how much have you actually increased that timing? At breakfast time I need 45mins prebolus with Fiasp (and a low carb berries and yoghurt breakfast) unless my levels are in the 4s to start with and then just 30 mins but with NR (not "Rapid" at all
🙄 ) I needed 75 mins most mornings to prevent my levels spiking. I also find it is very important to inject before I get out of bed because once my feet hit the floor, my levels start to rise and my insulin is fighting to overcome a strong tide of glucose release from my liver, so it needs as much of a head start as I can give it.
I am not saying you will also need such a massive prebolus time, but most people don't experiment beyond 30 mins and some people need longer, especially if your waking readings are a bit high to start with. Do be cautious if you intend on extending that prebolus time further and increase by just a few minutes each day until you find the right timing for you. I always make my breakfast and a coffee as soon as I get up, so that I have it ready in case my levels start to drop more quickly (less slowly
🙄) than usual but it is a pretty consistent 45mins for me with Fiasp. Lunch and evening meal are less at about 15-20 mins (used to be 30mins with NR) but breakfast needs A LOT longer and if my levels are 8 or above when I wake up, it will take longer still. I have waited a couple of hours before sitting looking at my breakfast when above 10..... but that is just me. You have to find what works for you.
When do you inject your Lantus? Just changing the timing of it might help to give you a peak of activity when your body needs it and a lull when it needs less. Just to clarify.... basal insulins often don't give you a steady release of insulin over their period of activity. I believe Lantus builds to a peak at about 5-8 hours, so it can sometimes help to adjust your dose time so that that peak in activity coincides with when you need it most.... For many people that is in the morning, so taking it last thing at night can be helpful for some people, but not everyone and others find, first thing in the morning works best for them. Partly it depends on what time you go to bed and when you get up.
What time of night do you get the "lows" and are they real lows (ie checked with a finger prick) or are you using Libre and if so, could they be compression lows where it gives an erroneous low reading due to lying on it?
If you are using Libre, would you like to post a typical graph showing these lows as sometimes you can tell from the shape of the graph if it is likely to be a compression low or an actual low. ie. if levels gradually fall throughout the night it is likely to be genuine but if the graph is steady and then dips and perhaps comes back up afterwards, that suggests you may have rolled onto your sensor during your sleep and then rolled off it again.
As mentioned by
@Inka, a change of basal insulin to Levemir might give you more flexibility to manage your day and night time levels if you can't find a timing and dose of Lantus that works for your body day and night. I love Levemir for the flexibility it provided me and I can reduce it when I am more active and increase it when I am more sedentary. For me this is usually adjusting my evening dose, as my daytime needs stay pretty constant regardless of what I do, but my body seems to readjust during the night and replenish stores used during the day. Other people find they need to reduce their daytime basal for exercise and/or adjust their meal boluses.
Anyway, interested to know how you got on with your basal testing, so do let us know, but those were just some thoughts from reading your post.
