Are you aware of insulin shock?

Diabetes nurse educator, Kate Bristow, educates us on what insulin shock is, the causes and how to spot it before it leads to hypoglycaemia.

What is insulin shock?

Insulin shock is caused by having too much insulin in your bloodstream. It can lead to hypoglycaemia (low blood glucose).

It can happen if you:

  • Ignore the signs of an early hypoglycaemic event.
  • Mistakenly take too much insulin.
  • Miss meals or eat too little to cover the insulin dose (fasting).
  • Do more exercise than usual and have not eaten enough carbohydrate (CHO) to cover the exercise or changes to a new exercise routine.
  • Drink alcohol without eating any, or enough food.
  • Have hypoglycaemic unawareness which can happen sometimes if you have had diabetes a long time. In other words, you don’t feel the low coming on.
  • Are unwell.
  • Are working so hard at managing your diabetes well (but don’t ever stop working at this).

Insulin shock is a diabetic emergency and can lead to diabetic coma, brain damage and even death.

How does it happen?

Insulin is normally made in the pancreas and is a necessary ingredient to allow the glucose in the bloodstream to enter the cells.  In someone without diabetes, the body does this automatically without you knowing about it, but in people with diabetes, it’s your job to give your body just the right amount of insulin to move the glucose from the bloodstream to your cells where it gives you the energy to function. Tough job, right?

Remember glucose is fuel for the body. If you have too much insulin in your system or you have done more physical activity and used up more of your glucose store, or perhaps not eaten enough carbs to cover the insulin you have injected, you may have a low or a hypo.

How do you recognise the signs of insulin shock?

If your blood glucose drops just a bit below normal (4mmol/L), your symptoms may be mild (Mild hypoglycaemia)

  • Dizziness
  • Shaking
  • Sweating or a clammy feeling
  • Hunger
  • Anxiety
  • Irritability
  • A rapid pulse

This is where normally you can reverse the symptoms using the 15/15 rule.

  • Have 15g quick-acting CHO (sugar, sweets, Coke, or fruit juice).
  • Have a small healthy snack to help your body recover.
  • After 15 minutes test your blood glucose again to see if it has improved.
  • If it still has not increased, then have another 15g of quick-acting CHO.
  • Keep testing until your blood glucose has stabilised.

A blood glucose level that is dropping fast can also cause:

  • Headaches
  • Confusion
  • Fainting
  • Tripping, falling and lack of coordination
  • Muscle tremors and seizures
  • Possible coma
  • If it happens when you are asleep, it may also manifest as nightmares, crying out in your sleep or waking with sweating and confusion and possible aggression.

How do we treat insulin shock?

  • If the person is experiencing the symptoms above, treat with the 15/15 rule.
  • But if they are unconscious, call emergency services immediately.
  • Don’t give an unconscious person something by mouth as they may choke.
  • Administer glucagon if you have it available. If not, the emergency response team will have some.

How to stop insulin shock from occurring?

Prevention is always better than cure. So, always carry a hypo kit with you so you can respond immediately if your blood glucose dips too low. Your hypo kit should include your test meter, some quick-acting CHO as well as a longer-acting snack in case you are out and about (Futurelife High Protein Bars or a piece of fruit are good options).

Eat after taking your insulin and work to count carbs correctly so you don’t give too much insulin.

If exercising, you may need to adjust your insulin dose before and after the session. Discuss how to do this with your diabetes team, doctor or diabetes nurse educator.

Be cautious when drinking alcohol.

Test your blood glucose often; a continual glucose monitor (CGM) can be useful too.

Test your blood glucose levels before you drive or operate heavy machinery.

Teach your family and friends about hypoglycaemia and how to help you fix it should it occur.

Always have a glucagon injection available.

Wear a medic alert identification; ICE medical bracelets have a great range to choose from.

Sister Kate Bristow is a qualified nursing sister and certified diabetes educator.


Kate Bristow is a qualified nursing sister and certified diabetes educator. She currently runs a Centre for Diabetes from rooms in Pietermaritzburg, providing the network support required for the patients who are members on the diabetes management programme. She also helps patients who are not affiliated to a diabetes management programme on a private individual consultation basis, providing on-going assistance and education to assist them with their self-management of their diabetes.

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