The ﬁrst time a person with diabetes gets a low glucose
reaction—usually at a glucose level of about 54 mg/dl, he or she usually gets shaky, sweaty, and hungry.
Other symptoms include anxiety and nausea. These are very uch like the symptoms you get when you are extremely nervous and are
called autonomic symptoms. It’s your body’s way of telling you that your glucose is low and you should eat.
If these autonomic symptoms are ignored, the glucose levels fall into a range where the brain is starved of
energy (around glucose value of 49 mg/dl) and you feel irritable, you can’t think clearly, your vision is
blurred, you feel tired, you have a headache, and you have difﬁculty speaking. These are called
neuroglycopenic symp-toms . When the
symptoms are severe, they can prevent you from treating the low glucose levels, and if the glucose level
falls even further, into the less-than-30 range, you can lose consciousness or even have a
If you have had diabetes a very long time and/or have had several
recent low glucose reactions, you may not get the autonomic symptoms, or they may occur at lower glucose
levels. So often the ﬁrst indication that your glucose is low may be neuroglycopenic symptoms such as feeling
tired or having blurred vision. Occasionally patients tell that they had a glucose
measurement in the 30s and they felt ﬁne. This inability to recognize hypoglycemia until the levels are very
low is known as hypoglycemic unawareness, and it is of concern because the glucose levels only have to fall a
little further before there is loss of consciousness.