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Questions About Insulin for and from Your Doctor

If you were buying a car, you wouldn't dream of leaving the showroom without first asking the salesperson how safe it is, how well it drives, and how to operate it.

If you've been prescribed insulin -- a medicine used to treat diabetes -- you shouldn't consider leaving your doctor's office without asking how to take it, what side effects it might have, and how it will affect your diabetes.

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Here is a list of important questions to ask your doctor before you start taking insulin: 

What type of insulin do I need?

Insulin comes in four basic forms:  

  • Rapid-acting insulin starts working within a few minutes after injection, but its effects only last for a couple of hours.
  • Regular- or short-acting insulin takes about 30 minutes to work fully and lasts for 3 to 6 hours.
  • Intermediate-acting insulin takes 2 to 4 hours to work fully, and its effects can last for up to 18 hours.
  • Long-acting insulin takes 6 to 10 hours to reach peak levels in the bloodstream, but it can keep working for an entire day.

Ask your doctor which of these insulin forms will work best with your diabetes type and blood sugar level.

Which insulin delivery method should I choose?

To inject insulin, you can use a syringe, pen, or pump. There is also a needle-free option called a jet injector. Discuss with your doctor the pros and cons of each method. Pens are easiest to use, pumps deliver insulin continuously, and syringes are the least expensive. 

A rapid-acting inhaled insulin is also FDA-approved for use before meals only in people with both type 1 and type 2 diabetes. For those with type 1 diabetes inhaled insulin must be used in combination with long-acting insulin . 

The decision may come down to cost, so find out which method your insurance will cover. If you don't have insurance or your plan won't pay for the type of insulin delivery method you prefer, ask your doctor about programs that can help you cover the cost.

How many times do I need to inject insulin each day?

People with type 1 diabetes may need up to three or four injections daily. Those with type 2 diabetes may need just one shot of insulin a day, possibly increasing to three or four injections.  

Find out how many times a day you'll need to inject, and how much insulin to inject in each dose. If you're using an insulin pump, ask your doctor when you'll need to give yourself an extra injection (bolus).

When should I take my insulin?

How often you take insulin depends on several factors, including:  

  • The type of insulin you use (fast-acting, premixed, etc.)
  • How much and what type of food you eat
  • How much exercise you get
  • Other health conditions you have
  • The type of insulin delivery system you use

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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