What is insulin?

Insulin

Insulin shots for children: Overview

Insulin is normally made by the pancreas, a gland behind the stomach. In children with type 1 diabetes, the pancreas no longer makes enough insulin or it stops making it. Without insulin, your child's blood sugar level rises to dangerous levels. When this happens, your child needs insulin shots to keep blood sugar at a safe level.

You may be nervous giving your child a shot at first. But soon, giving the shot will become routine. It is quite easy to learn how to draw up insulin into a syringe and give the shot. The needles you use to give the insulin injections are very thin, and most children who have diabetes say that they do not even feel the needle enter the skin. Even if your child does feel the injection, the sting of the shot is not bad and does not last long. Many parents give their children shots. You can too.

How can you store insulin and prefill syringes?

Insulin can become damaged and ineffective if it is not stored properly.

  • Unopened insulin that is packaged in small glass bottles (vials) should be stored in the refrigerator.
  • Liquid insulin that is packaged in small cartridges (containing several doses) is more stable. These cartridges are used in pen-shaped devices (insulin pens) with attached disposable needles. Keep unopened pens and cartridges in the refrigerator. After you open them, store them at room temperature.
  • Powdered insulin cartridges are packaged in blocks of three on cards sealed in foil. Keep unopened foil packages in the refrigerator. After you open a foil package, use the contents within 10 days. And after you tear off and open a block of three, discard any unused insulin after 3 days.

Always read the insulin package information that tells the best way to store your insulin.

You can keep open bottles with you if you keep them in a dark place. The bottles should not be exposed to temperatures below 36 F (2.2 C) or above 86 F (30 C) . Never leave insulin in the sun or in your hot car, because sunlight and heat reduce the strength of the insulin.

Avoid shaking insulin bottles and liquid insulin cartridges too much to prevent loss of medicine strength and to prevent clumping, frosting, or particles settling out. Follow the storage information provided by the manufacturer.

The first time you use an insulin bottle, write the date on the bottle label. Always store an extra bottle of each type of your insulin in the refrigerator.

If you cannot prepare an insulin dose but can give the injection, you may need someone to prepare your insulin dose for you. A family member, friend, or health professional can prefill insulin syringes for you. If you prefill syringes:

  • Store the prefilled syringes in the refrigerator with the needle pointing up to prevent insulin from blocking the needle opening. Syringes filled with one type of insulin (rather than mixed insulin) will keep for about a month. Read and follow all instructions on the label.
  • Store different doses separately. For example, if your morning dose is different from your evening dose, have a different container for morning and evening injections.
  • Before using a prefilled syringe, allow the syringe to warm for 5 to 10 minutes. Gently roll the syringe between your hands to warm the insulin. If the syringe contains a cloudy insulin, make sure all of the white powder is dissolved before giving the shot.
  • Another option is to use an insulin pen. You do not have to put insulin into a syringe. You put a cartridge of insulin into the pen. Don't share insulin pens with anyone else who uses insulin. Even when the needle is changed, an insulin pen can carry bacteria or blood that can make another person sick.
  • With a disposable pen, a set amount of insulin comes in the pen ready to use. When the insulin is used up, you throw the pen away. You use a new pen the next time you need insulin.
  • Before their first use, insulin pens or cartridges are stored in the refrigerator. After that, you can store them at room temperature. They generally expire within a month after you open them. Follow the directions for storing and using the insulin.

What is the insulin-to-carbohydrate ratio?

The insulin-to-carbohydrate ratio is a formula used to find the amount of insulin you need. This amount is based on how many grams of carbs you eat at a meal or snack. Using the ratio allows you to adjust the amount of insulin you take so you can keep your blood sugar at your target level.

You and your doctor or diabetes educator will find your personal ratio by keeping track of the food you eat and testing your blood sugar level after meals.

Your insulin-to-carbohydrate ratio may change over time. In some people it will change from one meal to the next. For example, you might take 1 unit of insulin for every 10 grams of carbs for lunch but take 1 unit for every 15 grams at dinner.

How is insulin used to treat type 1 diabetes?

Insulin helps keep your blood sugar level within a target range. It can be taken as a shot (injection) or through an insulin pump. Rapid-acting insulin is also available as a powder that you inhale.

Most people who have type 1 diabetes take a combination of types of insulin. For instance, they may take a long-acting insulin once or twice a day and a rapid-acting insulin before each meal. The amount and type of insulin needed varies for each person.

  • The amount and type of insulin you need changes over time. It depends on your age, hormones (such as during rapid growth or pregnancy), and changes in exercise routine.
  • You may need higher doses during times of illness or emotional stress.

Never skip a dose of insulin without the advice of your doctor.

Types of insulin

Insulin is used to treat people who have diabetes. How quickly insulin starts to work and how long it lasts will be different depending on the type of insulin you use. Other factors that can affect insulin and your blood sugar are exercise, diet, illness, some medicines, stress, the dose, how you take it, or where you inject it. The table below is a general guide. Your results may be different.

Insulin is available in several strengths. U-100 is the most common. U-100 means there are 100 units of insulin in one milliliter of fluid. Other strengths include U-200, U-300, and U-500. For example, U-500 is five times more concentrated than U-100 regular insulin. Be sure to check the concentration of your insulin so you take the right amount.

Insulin is made by different companies. Ask your doctor or diabetes educator about the type of insulin you have and how to use it. See the table below for types of insulin and some examples.

Types of insulin
Rapid-acting insulins (bolus insulin) are usually taken at the start of a meal.

Insulin aspart (Fiasp)

Insulin glulisine (Apidra)

Insulin lispro (Humalog)

Clear 10–20 minutes 2–4 hours
Rapid-acting insulin also comes in a form that can be inhaled through the mouth. Insulin human inhalation powder (Afrezza) Contained in a cartridge 12 minutes 1½–3 hours
Short-acting insulins (bolus insulin) are usually taken a short time before a meal.

Insulin regular (Humulin-R U-100, Novolin R, and Novolin R ReliOn)

Clear 30–60 minutes 5–8 hours
Intermediate-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Insulin NPH (Humulin-N, Novolin-N, and Novolin ReliOn)

Cloudy 1–3 hours Up to 24 hours
Long-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Insulin detemir (Levemir)

Insulin glargine (Lantus and Basaglar)

Insulin regular (Humulin R U-500)

Clear 60–90 minutes (30 minutes for U-500) Up to 24 hours
Ultra long-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Insulin degludec (Tresiba)

Insulin glargine (Toujeo)

Clear 1 hour (up to 6 hours for insulin glargine) 36–42 hours

Mixtures of insulin can sometimes be combined in the same syringe, for example, intermediate-acting and rapid- or short-acting insulin. Not all insulins can be mixed together.

For convenience, there are premixed rapid- and intermediate-acting insulins. These come in a premixed ratio, such as 75/25, 70/30, and 50/50. For example, 75/25 means the mixture is 75% intermediate-acting insulin and 25% rapid-acting insulin. They are usually taken 2 times a day at the start of a meal. These insulins look cloudy. The insulin will start to work as quickly as the fastest-acting insulin in the combination. It will last as long as the longest-acting insulin. Examples include:

  • Insulin regular and insulin NPH.
  • Insulin lispro and insulin lispro protamine.
  • Insulin aspart and insulin aspart protamine.

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