@DanisV
For me, 20 mins brisk walking will bring my BG down by 3 or 4 mmol straight away.
Sorry, I don’t know rules when to go to hospital- if you were in UK could telephone NHS 111 for advice - do you have an equivalent 24hour help line?
Sorry
@Ledzeptt , for a Type1 then
you should not exercise if your blood sugar is over 15!
Especially not so if you also have ketones!
It is a situation where you clearly do not have enough insulin available and your bg level will typically even increase further due to the exercise you do. Stimulated by the demand from your exercising muscles your body will pour glucose into your bloodstream (from liver and muscles). But your advice to drink water is always a good thing, to help your body to flush out the surplus sugar/ketones and support your kidneys as much as possible in the filtering job.
But now back to
@DanisV's question regarding going to the hospital for correcting a high or not? Well its definitely always depending on your own individual situation, how well you feel and how assured you are to make self-corrections at home, etc.
But first off, 15mmol/L is no emergency life threatening situation. Far from it actually! (except if its been like that for a very long time and you have ketones raising up, but your description does not indicate that to be the case, as severe nausea, vomiting etc should then also be there). Most Type1s have tried from time to time to have an off-day, where for whatever various reasons we get our insulin therapy wrong and the bg goes up like a spacerocket and we take a few hours or a day or two before we get it down again within the 'allowed range' of max 10mmol/L. Most types1s will typically take the necessary corrective fast acting insulin at home. Especially so, when having the routine and knowledge about determinating the required dose of fast acting based on the knowledge how much 1 unit of fast acting will drop their bg down. Personally mine drops around 3 mmol/L per units of fast acting. So if I measured I was up at e.g. 20mmol/L, then I would take 4 units of fast acting. And then set an alarm or be cautious to measure your bg 1 hour later to check the status and trend. You may at that time observe if you should take a little bit more or you should wait another 1 hour before doing so, if the bg has already dropped down considerably to be near your 10mmol/L mark. Always keep in mind that the injected bolus may take 2-4 hours before its full effect has incurred. It should also be observed that typically you will need more insulin units to drop your bg by a fixed mmol/L when your bg level is higher than 12 mmol/L. Aka, so you are more insulin sensitive when your bg is in the sweet spot zone of 4-8mmol/L and less insulin sensitive when your bg is too high.
