Lots of highs and lows this week

My daughter has been over 200 a few times every day this week and once she was just over 300. We never have had this problem before though we have only been at it since May. When we correct she winds up low. She even gets low when we under correct. For example she was over 250 at school. We are supposed to give one unit for every 50mg/ over 200. She took one unit and was in the 60's an hour later.

I think her Lantus is okay because she has been steady all night and wakes up at about 120. This has been climbing a bit from around 90 to100 but we are reluctant to add another Lantus unit until we are sure she is waking above 120 every morning.

Any ideas why she seems to need more Humalog but when we correct her sugar really drops so much?

Maybe this is the end of the honeymoon.

Terry,  there could be a lot of things at play here.  I have absolutely no medical training, so please take what I say with a grain of salt.  If this were me, here's what I'd be thinking:

What is the proximity of eating to these high numbers?  If they are within two hours of eating, it could be an issue of timing.  Doing her Humalog 10 - 15 minutes out could help if those 200 and 300's are a post-prandial peak. 

If those high numbers are not within two hours of eating, it sounds like a Lantus problem.

It could also be the case that her correction factor is too sensitive.  Perhaps she needs 1 unit for every 60 or 70 mg/dL, for example.

Have you mentioned this occurence to her endo/CDE/whoever you work with?

We wait to test until 2 hours after she eats.

Just last week one one unit per 50mg was okay. ( unless she was about to exercise). Now one unit brings her down over 140 mg/dl. This was two hours after eating.

It seems that the effects of exercise last for many hours for her.

How long should we wait to test after giving a correction?Is it two hours like after eating?

We went from excellent control to out of control in a week.