All about insulin

Insulin helps turn food into energy

Insulin is a hormone made by the body. It allows glucose from foods you eat to move out of your blood and into your body’s cells. Your cells use this glucose for energy.

When you live with diabetes, your body doesn’t make enough insulin, or any at all. The insulin it does make may not work well. So, glucose stays in the blood instead of going into your cells, leading to high blood glucose levels. 

Your doctor or nurse practitioner may prescribe you with insulin to help keep your blood glucose levels in your target range, and reduce your risk of diabetes-related complications.

Insulin can be used to manage all types of diabetes

Insulin is very effective at lowering blood glucose levels.

No matter what type of diabetes you have, you may need to start insulin at some point. This does not mean you have the “bad” type of diabetes or that you have failed at managing your diabetes.

Type 1 diabetes 

All people with type 1 diabetes must take insulin. This is because the immune system has destroyed the body’s ability to make insulin. 

Type 2 diabetes 

Many people with type 2 diabetes need to take insulin.

While healthy eating, regular physical activity and glucose-lowering medicines can be used to manage type 2 diabetes for some time, many people will need to start insulin at as their diabetes progresses. 

Gestational diabetes 

Many people with gestational diabetes will need to use insulin during their pregnancy until after the baby is born. 

This is because pregnancy hormones can make it harder for the body to use insulin properly, leading to high blood glucose levels. 

Different types of insulin are used to manage blood glucose levels

There are three main types of insulin used for diabetes. You may need more than one type of insulin to keep your blood glucose level in your target range. This will depend on the type of diabetes you have and your diabetes management plan. 

Your doctor or diabetes nurse practitioner will prescribe the insulin that is best for your goals and lifestyle. They will also show you how to use your insulin. 

Insulin is taken by injection or with an insulin pump

Insulin cannot be taken as a tablet. It must be injected with a pen device or a syringe, or with an insulin pump. 

Insulin works best when it is injected into the fatty layer under the skin, usually in the abdomen (tummy) area. In some cases, the thigh or buttocks (bottom) may be used.  

Diabetes educators can help you choose the right injection device for you and show you how to inject insulin safely.  

Check you are using the right dose and type of insulin before you inject

It is important to take insulin exactly as prescribed. Before you start, check you are giving the right amount and type of insulin for that time of day.

This is extra important if you use more than one type of insulin or different doses over the day.

Other things to check before you inject

• Expiry date. Do not use the insulin after the expiry date shown on the label.
• Appearance. Do not use the insulin if it does not look the way it should. For example, if the insulin is a different colour, has lumps or flakes, or your clear insulin has turned cloudy.
• Temperature. Do not use insulin if it has been frozen or left in the heat.
• Injection site. Avoid areas where there are scars, stretch marks or lumps. Do not inject through your clothes.

If you make a mistake with your insulin, act quickly

Mistakes happen, and if you accidentally take the wrong amount or type of insulin, keep calm and know what to do next.

If you take too much

Having too much insulin can happen if you accidentally give the wrong dose, or if you do not eat enough carbohydrate foods to match your insulin dose.

This can cause your blood glucose level to drop too low (below 4 mmol/L for most people). Low blood glucose is called hypoglycaemia or a “hypo” for short.  

It is important to quickly treat a hypo with fast-acting carbs like jellybeans or sweetened drinks, as untreated hypos can be dangerous. 

If you take too little

Having too little insulin can happen if you forget to take your insulin, give the wrong dose, or eat more carbohydrate foods than usual.

This can cause your blood glucose level to become too high, which is called hyperglycaemia. You may also need more insulin when you are unwell.

Ask your diabetes health professional for instructions on what to do if you do not take enough insulin, have high blood glucose levels, or are unwell.

Do not take a missed dose or extra insulin unless your diabetes health professional has advised you to.

Store insulin correctly to make sure it keeps working well

Insulin that is not stored correctly can get damaged and stop working properly.

Dispose of sharps properly to keep your community safe

A sharp is any syringe, pen needle, finger prick needle, needles used in insulin pumps, and sensors for continuous glucose monitoring (CGM). Disposing of sharps properly helps keep other people and the environment safe.

Tips for disposing of sharps safely

• Handle your sharps carefully. 
• Always place your used sharps in Australian-standard approved sharps containers. These containers are available from a NDSS Access Point (usually a community pharmacy). 
• Do not use glass or cardboard containers, tins, or plastic bottles as sharps containers. 
• Take your used sharps containers to a designated disposal facility, such as some public hospitals, participating pharmacies and medical centres, community sharps disposal bins and some councils. 

When to see a health professional

Make an appointment if you are having frequent low or high blood glucose levels, or if you have any questions about your insulin.

Your insulin needs can change over time. See your diabetes health professional regularly so they can review your diabetes management plan.