Ketoacidosis (DKA): the slow emergency

Diabetic ketoacidosis — DKA — is the slow emergency. It builds over hours rather than minutes, it does not fix itself, and it needs a hospital. This page covers what causes it, the signs, and exactly when to stop waiting and go in.

What it is

When there isn't enough insulin working, ketones build up and the blood turns acidic. The usual routes in are:

• missed insulin
• illness, which raises insulin needs even when you are not eating
• a pump failure — with no long-acting insulin underneath, ketones can climb fast

The signs

• stomach pain
• vomiting
• sweet-smelling breath
• fast, deep breathing
• thirst
• drowsiness

Why it gets this much attention

Of the years of life lost before fifty in Scotland's national type 1 data, the largest single share came from DKA and diabetic coma — not from eyes, kidneys or nerves.

DKA is acute, fast and preventable. Delay is what makes it dangerous. That makes sick-day rules and ketone strips the part of diabetes education that saves the most life-years — and the part most often skipped. Most patient material gives DKA a footnote and eye disease a chapter; for young people, the evidence says to do the reverse.

When to go in

Nobody has ever been in trouble for arriving at an emergency department with ketones. If you are unsure, going in is the right call.

Preventing it

Three habits are the core of prevention:

1. Never stop long-acting insulin — not even when you are too sick to eat.
2. Check ketones when you are unwell, whatever the glucose says, and keep in-date ketone strips at home.
3. Have a written sick-day plan from your diabetes team before you need it.

The details are on the sick days page. Some medications can also bring on DKA even at a normal glucose reading; the Medications section covers that.