The investigators know that intensive insulin therapy and tight glucose control is associated
with reduction of diabetic complications. However, many patients on insulin don't achieve
this because of the risk and the fear of hypoglycaemia (too low blood glucose).
There has been a lot of work done recently looking at the mechanisms by which the brain
detects hypoglycaemia. A key player is a potassium channel in the brain (KATP channel).
Studies have shown that when these channels are opened, there is a release of hormones such
as adrenaline that can help in raising blood sugars to counteract and increase awareness of
hypoglycaemia. The investigators study aims to look at an old drug called diazoxide, which is
able to open KATP channels.
The investigators aim to see if diazoxide will amplify the release of hormones such as
adrenaline when the blood sugar is low. If this is the case, this will aid quicker recovery
following hypoglycaemia.
The investigators aim to do this by performing a well established experimental protocol that
has been performed safely over the last 20 years called a clamp study. The clamp study will
involve slowly bringing the blood sugars down using insulin and intravenous glucose in a
controlled fashion. The main outcome will be the hormonal responses (adrenaline response) at
a blood sugar level of 2.5mmol/L. Symptoms of hypoglycaemia will be monitored, as well as
working memory tests using standardised questionnaires.
The design of the investigators study will be a randomised trial comparing the effects of
diazoxide with placebo in which all patients will receive both diazoxide and placebo in
random order (crossover design).