Insulin is the primary medication used to treat type 1 diabetes. Another injectable hormone made in the pancreas, pramlintide (Symlin) has also been approved for the treatment of type 1 and type 2 diabetes for patients who also already take insulin. Here is information for both treatments.

The information provided here is meant to give you a general idea about each of the types of insulin listed below. Only the most general instructions are included, so ask your doctor if you need to take any special precautions. Use each of these medications as recommended by your doctor or according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.


For proper diabetes control, insulin is administered by injection several times throughout the day to replace the insulin that the pancreas is unable to produce. Insulin must be taken as an injection, because if it were taken by mouth, it would be digested by the enzymes in the stomach before it reached the bloodstream.

Insulin Injection Sites

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The amount of insulin you take must be balanced with the amount and type of food you eat and the amount of exercise you do. If you change your diet, your exercise, or both without changing your insulin dose, your blood glucose level can drop too low or rise too high.

Before getting insulin, you should check your blood glucose level with a blood glucose meter. This will help you to determine how much insulin you need. You can also ask your doctor about continuous glucose monitoring systems (CGMS) that you wear all day.

Most individuals with type 1 diabetes will need two to four insulin administrations daily. Current insulin treatment regimens usually employ some combination of rapid-acting and long-acting insulin. Insulin is most commonly administered before meals, sometimes at snacks, and at bedtime.

All About Insulin

The three characteristics of insulin are:

Onset—the length of time it takes for the insulin to reach the bloodstream and begin lowering blood glucose after it is injected

Peak Time—the time during which insulin is at its maximum strength in terms of lowering blood glucose levels

Duration—how long the insulin continues to lower blood glucose

Main Types

The main types of insulin available are:

Type of insulinOnset*Peak time*Duration*Notes on use
Rapid-actingNovolog (aspart) Humalog (lispro) Apidra (glulisine)10-30 minutes0.5-3 hours3-5 hoursInject immediately before a meal.
Regular or short-actingNovolin R Humulin R0.5-1 hour2-5 hours5-8 hours 
(NPH )
1-2 hours3-12 hours18-24 hoursThis is often used in combination with short-acting insulin.
Insulin glargine (Lantus), Levemir (detemir)
1 hourn/a24 hoursThis may not be mixed with other types of insulin.

*Each person has a unique response to insulin, so the times mentioned here are approximate.


Premixed insulins are a mixture of short-acting and intermediate-acting insulins, usually given twice per day with breakfast and dinner.

Type of insulinOnsetPeak timeDuration
Humulin (50/50)30 minutes2-5 hours18-24 hours
Humalog mix (75/25)15 minutes0.5-2.5 hours16-20 hours
Humulin (70/30)30 minutes2-4 hours14-24 hours
Novolin (70/30)30 minutes2-12 hoursup to 24 hours
Novolog Mix (70/30)10-20 minutes1-4 hoursup to 24 hours

Common Brands

The table below shows types of insulin and common brand names.

Type of insulinBrand names
Rapid-acting Humalog (insulin lispro)
NovoLog (insulin aspart)
Apidra (glulisine)
*both require a prescription
Regular or short-acting Humulin R (regular)

Novolin R
Intermediate-acting Humulin N (NPH)

Novolin N (NPH)
Long-acting Levemir (detemir)
Lantus (insulin glargine)

Humulin R 500 and Lantus U-300 are insulins that require special instruction from your doctor.

Methods of Insulin Delivery

The following lists ways of getting insulin through the skin.

Syringe and vial—The syringes you will use are small and have fine points and special coatings that help make injections as easy and painless as possible. When insulin injections are done properly, most people find that they are relatively painless. Insulin is usually given as a subcutaneous injection. This means that the needle goes into the fat layer between the skin and the muscle to deliver a certain amount of medication.

Pen—The insulin pen looks very much like an old-fashioned cartridge pen, except that it is disposable, has a needle, and holds a pre-filled cartridge of insulin. Pens are particularly useful for people who travel frequently, whose coordination is impaired or have visual difficulties. They are also more useful for people who require very small doses of insulin.

Pump—This is a computerized device about the size of a beeper that is worn on the belt or in a pocket. It delivers a steady, measured dose of insulin through a flexible plastic tube called a cannula. With the aid of a small needle, the cannula is inserted through the skin, usually in the abdominal region, and is taped in place. In some products, the needle is removed and only a soft catheter remains in place. Based on your meals and your blood sugar level, you control the release of insulin from the pump. Because the pump continuously releases tiny doses of insulin, this delivery system most closely mimics the body's normal release of insulin. Pumps can deliver very precise insulin doses for different times of the day, which may be necessary to correct the dawn phenomenon—the rise of blood sugar that occurs in the hours before and after waking.

Special Considerations
  • Check your insulin's expiration date. If you have not finished it before it expires, throw the rest away.
  • Store unopened bottles of insulin in the refrigerator. Do not store your insulin at extreme temperatures.
  • Keep the bottle of insulin you are using at room temperature. Injecting cold insulin can sometimes make the injection more painful. (Most doctors believe that insulin kept at room temperature will last 1 month. Check with the information on your glucose to make sure.)
  • If your treatment requires that two different insulins be mixed, be sure that you understand which of the two should be drawn into the syringe first. If you change the mixing pattern, you may change the dose you receive. Some insulins cannot be mixed together. Do not mix insulins together in one syringe unless you have been instructed to do so.

Common name: pramlintide (Symlin)

Amylin is a hormone produced by the same beta cells which produce insulin. In fact, amylin is released into the bloodstream at the same time as insulin. Amylin reduces glucagon’s release and enhances a sense of fullness after ingesting a meal so you will eat less. Together with insulin, it lowers blood glucose. Pramlintide is chemically related to amylin.

Pramlintide is used together with insulin. It is given to patients who fail to achieve the optimal blood glucose levels despite getting the right dose of insulin. This drug is given by injection immediately before meals. It should be used with care in the elderly.

Pramlintide reduces appetite and is associated with modest weight loss. This can be very important since weight gain is one of the common side effects of insulin treatment.