Insulin FAQs – Type 1 Diabetes

When a child is diagnosed with a lifelong condition such as Type 1 Diabetes, it takes a toll on both the parents and the child. Although it can seem very daunting to administer insulin to your kids regularly, most parents and caretakers have to do so to ensure that no long-term or short-term complications occur.

Since this is such a vital part of managing diabetes and has its own set of dosages and administration techniques, it’s natural to have a lot of questions regarding insulin.

To make things easier for you, we’ve compiled a list of the most frequently asked questions regarding insulin and its use. Hopefully, this will help answer some of your doubts.

Insulin FAQs

We’ll try to address the more basic and commonly asked questions about insulin. 

You’ll find the answer to what types of insulin are available, how you can use them in terms of administration and dose calculation, and how you need to store the insulin. We also touch on the implications of administering too much or too little insulin. 

1. What Are the Types of Insulin?

Insulin can be divided into categories based on how quickly it works and how long its effects last. Note that the details below are rough estimates. There are a number of other factors that affect insulin uptake time that are too numerous to mention here. These estimates are sufficient for a high level understanding of the differences between insulin types.

Rapid-acting Insulin

• Enters the bloodstream – 15 minutes after administration.
• Reaches peak levels – 30 – 90 minutes after administration.
• Stays in the bloodstream – Two to four hours. 
• Available options – Insulin Aspart, Glulisine, and Lispro.

Since they work quickly, they mimic how normal insulin would work after a meal, hence they are used 15 minutes after a patient with diabetes has taken a meal. 

Regular or Short-acting Insulin

• Enters the bloodstream – 30 minutes after administration.
• Reaches peak levels – Two to four hours after administration.
• Stays in the bloodstream – Three to six hours. 
• Available options – Human regular Insulin. (Humulin R, Humalog R, Novolin R, etc.)

Intermediate-acting Insulin

• Enters the bloodstream – Two to four hours after administration.
• Reaches peak levels – Four to 12 hours after administration.
• Stays in the bloodstream – 12 – 18 hours. 
• Available options – NPH (Neutral protamine Hagedorn) Insulin.

Long-acting Insulin 

• Enters the bloodstream – Two hours after administration.
• Reaches peak levels – Do not peak.
• Stays in the bloodstream – Up to 24 hours. 
• Available options – Insulin Degludec, Detemir, and Glargine. (Lantus, Toujeo, Levemir, Tresiba, etc.)

These insulins are usually referred to as “basal” insulins that act in the background. A basal insulin is combined with a “bolus” insulin that is short- or intermediate-acting.

Ultra Long-acting Insulin 

• Enters the bloodstream – Six hours after administration.
• Reaches peak levels – Do not peak.
• Stays in the bloodstream – Up to 36 hours. 
• Available options – Insulin Glargine U-300.

Often various formulas are available in combinations to provide maximum glucose control. There are three main combinations.

1. Rapid-acting and Intermediate-acting insulin.
2. Rapid-acting and Long-acting insulin.
3. Short-acting and Intermediate-acting insulin.

Gluroo allows you to easily track which type of insulin you’re using, whether it’s rapid acting, long acting, or regular acting.

2. How are Insulin Doses Calculated?

Insulin dosage is a bit complex and can seem very confusing at first. You must ask your (or your child’s) doctor to help adjust the doses before you can start doing it. What follows is only a basic approximation for educational purposes only. 

Having said that, these are the basic formulas you can follow.

Your total daily dose (TDD) of insulin is generally approximated by:

Weight in Pounds ÷ 4 = Total Daily Dose Insulin Requirement (in units of insulin)

Basal insulin is what will give you glucose control between meals and at night. 

This is generally 40-50% of your TDD.

Bolus insulin provides glucose control for meals and other carbohydrate intake. It also is used to correct for high blood sugar levels. One unit of rapid-acting insulin will usually account for 12-15 grams of carbohydrates, though it can vary widely from person to person and throughout the day.

Bolus insulin is generally 50-60% of the required insulin. The formula is below.

Total grams of Carbohydrates in the meal ÷ Grams of Carbohydrates accounted for by 1 unit of insulin = Bolus insulin dose (Carbohydrate Coverage)

3. How Is Insulin Administered?

Over the years various insulin delivery methods have been created to minimize discomfort in patients and make the process easier. There are three main ways to inject insulin. 

• Insulin Syringes – This is the classic method of administration and comes in three volumes to hold the insulin. You fill the syringe up with insulin that comes in vials. Syringes have various needle thicknesses or gauges ranging from those for infants to adults. They can be disposable or reusable and can be used to inject insulin into the fat under the skin (subcutaneous tissue). 
• Insulin Pens – Pens are now very common due to how easy they are to use. They contain a cartridge that has a measured amount of insulin, and you can use a dial to choose the dose. In reusable pens, the cartridge is replaced after it’s empty, and the needle can be replaced too. These also inject the insulin subcutaneously with one simple click. 
• Insulin Pumps – Insulin pumps are the newest of these devices. They vary in size and are worn by the user in the stomach area or on the arm. They’re programmed to deliver a specific dose of insulin at specific times subcutaneously. They give a basal dose to maintain glucose between meals and allow you to administer a bolus at mealtimes or as a correction.

The best sites for insulin administration are the abdomen, the back of the arm, and the thigh. Just make sure to change the injection site regularly so that it doesn’t become infected. 

4. Does Insulin Need to Be Stored in The Refrigerator? How Long Does It Last?

Insulin storage is a bit tricky because extreme hot or cold temperatures can affect the quality of the insulin. But here are a few simple rules-of-thumb regarding how you can store insulin. 

• You can easily store unopened insulin up to its expiration date in a refrigerator at a temperature between 2 and 8 °C or 36°F to 46°F. 
• Do not freeze insulin and never use insulin that has been frozen.
• Opened (cap is removed and the rubber stopper is punctured) and unopened insulin can be stored at temperatures under 25°C or between 59°F-86°F, but it is only usable for 28 days. After that, many manufacturers advise that you discard any remaining insulin.
• Once you have opened a vial or pen or cartridge, it can only be used for a limited amount of time based on the manufacturer’s instructions. Vials usually last 28 days after being opened and pens can last from 7-28 days. (Personally, I tend to keep insulin that is older than 28 days, despite the manufacturers recommendations.)
• It’s a good idea to keep some insulin handy when traveling and you can carry both opened and unopened pens and vials but make sure the temperature is under 25°C and the insulin is not exposed to sunlight.

Gluroo allows you to easily track your insulin pens and when you open them. That way, you can be sure how old they are and know when to stop using them.

5. How Many Units Are in a Vial of Insulin?

The standard U-100 vial of insulin contains 100 units of insulin per 1 ml of insulin. So, the commonly available U-100 vial of 10 ml has 1000 units of insulin in total.

The simple way to remember this is by remembering that the number after the U corresponds to the number of units in each ml of the vial. So, if someone says U-300 that means 300 units/ml. 

6. When Should Insulin Correction Doses Be Administered?

A bolus or correction dose may be needed to correct high blood glucose levels. In general, one unit of insulin may be needed to drop the blood glucose by 15-100 mg/dl or more. Again, this can vary greatly depending on the person, their activity levels, and so on.

A starting formula for a correction dose is:

Difference between actual blood sugar and target blood sugar ÷ Correction factor* = High blood sugar correction dose

*1800 ÷ Total Daily Insulin Dose = Correction Factor

Again, this is a very rough estimate. You should always clarify with your doctor about how to calculate basal, bolus, and correction doses. 

7. What Happens If I Take Too Much Insulin? And Too Little?

Taking too much insulin can be potentially fatal and is a medical emergency. Too much insulin can cause the patient’s blood glucose levels to drop dangerously low i.e. less than 70 mg/dl, which is known as hypoglycemia. In this case, the body won’t have enough glucose to function and you’ll have to correct it quickly. 

Some telltale symptoms of hypoglycemia are cold sweats, drowsiness, rapid heartbeat, confusion, blurring of vision, and jitteriness. If this happens, feed your child something sweet like glucose tabs, fruit juice, or candies like smarties or starburst. 

If someone administers too little insulin, it’ll lead to incomplete absorption of sugars into cells and cause abnormally high levels of glucose in the bloodstream. JDRF has a great overview of high blood sugar symptoms, causes, and treatments.

Gluroo Can Help You Keep Track of Insulin Doses

We understand that it can be very overwhelming and confusing when your child is diagnosed with Type 1 Diabetes, especially if no one else in your family has it, and this is a completely new topic for you.

With Gluroo, logging insulin doses (both basal and bolus) is quick and easy. Tracking insulin allows you to know how much insulin is still active in your child’s system. That, in turn, lets you predict where their blood glucose is heading, which can lead to better control, higher time in range (TIR), and less worry about diabetes.

Hopefully, this discussion allowed you to quickly get an idea of the basics of insulin and made you feel more confident about helping your child administer insulin at home.