Diabetes for the unfamiliar, in plain language:

1. Insulin helps get sugar into cells. Glucagon gets stored sugar out of the liver into the blood. Diabetes management in 2025 only deals with supplying external insulin.

2. There are several variants of diabetes. Type 1 is an autoimmune disorder where the body attacks the cells that make insulin.

3. Too much insulin equals all the sugar getting sucked out of your blood and lymph and into cells. This is really bad in an acute way. Your brain cannot run without sugar. Accidentally give yourself too much insulin for the sugars and wind up dead or in a coma in short order.

4. Highs are also bad, but generally in a less acute way. There are exceptions, but being too high with blood glucose for a period of time doesn't have the acute risks of being too low. Diabetics (or their caregivers) carry around quick absorbing sugar sources to help against a low.

5. The peak action (fastest reduction in blood glucose level) of the common insulin, in the way we dose it, peaks 90 - 120 minutes after the dose. The long tail is about 5 total hours of action from the point of dosing. So you should give insulin in advance of when you expect digestion to move glucose into your bloodstream. This is tricky. Also, as insulin ages, the peak of the action happens later. If a new vial is 90 minutes, an nearly empty vial might be 120 minutes after dosing for peak action.

6. CGMs, the on-body instrument in question here, are both flakey and amazing. There's a novel of good and bad here. I'm glad they exist, they can be cantankerous. They are a tiny potentiostat, if that is something you happen to be familiar with.

7. Very high blood sugar is treated with extra insulin to overcome the osmotic pressure of having too much glucose in the bloodstream. There's also a lot of chemistry here (glycocalyx to get you started). If your blood sugar is high you generally need more insulin to get past the hysteresis effects. Once the blood sugar starts to come down, that extra insulin is still around, and can cause a dramatic low. CGMs let you observe this, and "catch the low" by eating sugar to replenish the baseline sugar trapped in circulation.

8. Diabetes management is challenge every day, multiple times a day. Especially with small child who doesn't communicate to you about what they believe about their blood sugar. This is my personal circumstance.

9. Endocrinologists have suggested some wild stuff to my wife and I. For instance, keep a tube of cake icing around, as you can administer it rectally to a child who is passed out (or worse) from a deep low blood glucose. This is how poor the standard of care can be.

Father of 4.5 YO son with Type 1 diabetes, and materials engineer by education.

as a parent of a healthy child I was getting anxiety just from reading what you are going through with this. my dad and sister are diabetics but I can’t imagine dealing with a child…