I have noticed that my Lantus doesn't last 24 hours. Just found this out via my doctor recently! She didn't know this, or tell me for at least a year. For awhile I just took Lantus and no meal time insulin. I was happy thinking I only had to take one shot a day. My doctor also didnt understand how to dose. Very frustrating experience! It was recently suggested that I split my dose, but that would mean 5 shots a day. I don't want MORE shots, I want LESS! I take 24 units about 10am, it seems to peak at 3pm, and next morning I have a high BS reading!
I also find that I suffer from Darn Phenomenon (DP) and actually need more insulin overnight to combat the morning highs. In fact, it may be that the Lantus is lasting pretty much 24 hours, but you need more insulin overnight to fight the DP. You could try shifting the time you take your lantus to the evening and then you might be better able to deal with it only lasting part of the day. This would have it peaked overnight when you need it and then you could then adjust your dinner bolus to compensate for any rise late in the day.
At dsolve.com I found this:
"Lantus lasts about 22 hours in most people and Detemir lasts about 16. Either insulin can sometimes be given once a day successfully for some individuals but most people get on better with twice daily injections for both of them. The best time to give them is right before bed and when you get up in the morning. If you have a marked dawn phenomenon no more than a 9 hour gap between the night and morning injection is recommended by Dr Bernstein."
My endo at GW hospital in DC was also a big researcher. He told me straight out that Lantus will not work effectively as a basal for a whole 24 hours and should be split into two doses for a more stable blood glucose level all day and night. I dosed like that for years--it was one of the main reasons I went to a pump--too many shots.
Yes, when I was on Lantus I had to inject it twice per day as well. It only seemed to last about 20 hours for me otherwise and I had extreme highs during the time it "wore off."
I'm terrified. I was diagnosed as Type 2 a few years ago but it seems now that my pills are not working. They think my high blood sugars have ruined my beta cells. Now they are experimenting with Lantus. My fasting blood sugar is 290. HELP!