Insulin normally is made by the pancreas, a gland behind the
stomach. The medicine form of insulin helps the body use glucose. Insulin
cannot be taken as a pill, because stomach acid destroys insulin before it can
enter the blood.
Insulin is categorized according to how
fast it starts to work and how long it continues to work. The types of insulin
available include rapid-, short-, intermediate-, and long-acting insulin. See
types of insulin for more information. Insulin strength is usually U-100, but U-500 is also available, which is five times more concentrated than U-100. If you are very resistant to insulin, U-500 allows you to inject fewer units but get more of the medicine.
Insulin is packaged in small glass
bottles that are sealed with rubber lids. One bottle of U-100 insulin holds 1,000 units, which is
many doses of insulin. It is also packaged in small cartridges used in
pen-shaped devices (insulin pens) attached to disposable needles.
Insulin bottles and cartridges are labeled with
important information you should read, such as the expiration date.
How insulin is taken
Insulin usually is given as a
shot under the skin. It can also be given through an insulin pump or a jet injector, a device that sprays the medicine into the skin. Some insulins can be given in a vein, but this is only
done in a hospital.
How It Works
Insulin reduces blood sugar levels by
helping sugar (glucose) enter the cells to be used for energy. Sometimes women
gestational diabetes need to take two types of
insulin, usually a rapid- or short-acting and an intermediate-acting type.
Long-acting insulins have not proved to be safe for use during
The short-acting insulin reduces blood sugar
levels quickly and then wears off.
The combination of a rapid- or short-acting and
intermediate-acting insulin helps keep blood sugar levels in a
target range both before and after meals.
Why It Is Used
You will need to take insulin if changing the way you eat and getting
regular exercise do not keep your blood sugar in a target range. Keeping your
blood sugar in a target range is the best way to prevent problems from
gestational diabetes, such as a baby who grows too large or a baby who is born
with low blood sugar. Usually, gestational diabetes goes away after your baby
is born. Then you no longer need insulin.
Insulin is effective in reducing blood sugar levels by helping sugar (glucose) enter the cells to be used for energy.
All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
Usually the benefits of the medicine are more important than any minor side effects.
Side effects may go away after you take the medicine for a while.
If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.
Call 911 or other emergency services right away if you have:
Swelling of your face, lips, tongue, or throat.
Passed out (lost consciousness) or suddenly become very sleepy or confused. You may have low blood sugar, called hypoglycemia.
Call your doctor if:
You have hives.
You often have problems with high or low blood sugar levels.
Common side effects of this medicine include:
Low blood sugar.
See Drug Reference for a full list of side effects. (Drug
Reference is not available in all systems.)
What To Think About
What you need to know
Insulin will work faster if:
It is accidentally injected into a muscle instead of into fatty tissue.
You have just exercised the muscles in the area where you give your insulin
You put a heat pack on or massage the area where you have just given your
To learn how to prepare and
give insulin injections, see:
of insulin may not work well after 30 days. Label each insulin bottle the first
time you use it. Then after 30 days, throw away any insulin you did not use
from that bottle.
Always check the expiration date on the bottle.
Insulin should be
stored properly. If it is not, it may break down and
not work very well.
Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.
There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
How this information was developed to help you make better health decisions.