All you want to Know About Insulin

Insulin is a hormone produced by the pancreas which helps in controlling the blood sugar levels. All type 1 diabetic patients need to take insulin in order to maintain their blood sugar levels. Occasionally, type 2 diabetic patients with very high blood sugar levels those who don’t respond to any antidiabetic medications, are also prescribed insulin.

Insulin types

There are different types of insulin for diabetes depending on how quickly they start working, the time at which their action is at peak and how long the effect remains. Your doctor will decide on the type of insulin to be used for you. A mixture of different types of insulin may also be prescribed.

The table below will give you a general idea of the main types of insulin available.

Type of insulin Time of onset of action Peak time of action Total duration of action Dosing schedule Examples
Rapid-acting
Within 15mins
30mins to 3 hours
2-5 hours
Right before eating
Lispro, Aspart, Glulisine
Short-acting
30mins1 hour
2-4 hours
8 hours
30mins before eating
Regular (R) or Novolin
Intermediate acting
1-4 hours
4-12 hours
12-18 hours
30mins before eating, at bedtime or twice a day
NPH (N)
Long-acting
1-10 hours
No clear peak time of action as it remains in a steady state throughout
24 hours
Once or twice a day
Insulin glargine, Insulin detemir

Devices to deliver Insulin

In addition to the standard syringe and needle, there are many devices available to deliver insulin. They are: insulin pens, external insulin pump, and insulin ports. You can select the most convenient one for you.

Insulin Pens

Insulin pens look like a pen with a cartridge attached. They are easy to use, and cause less pain than the standard needle and syringe.

You have to screw a fine, short needle on to the tip of the pen and select the dose by adjusting the dial on the pen. Once you inject the needle into the skin, you have to press the plunger at the end of the needle to deliver insulin.

Insulin Port

An insulin port is a disposable device with its needle fixed to the skin’s surface. A small sheath is inserted into the port to deliver the insulin. This can be used for 3 to 5 days, and the port is then discarded. This device also prevents you from pricking every day.

Inhaled insulin

Now, we have a new, non-invasive way of administering insulin. Afrezza is an FDA approved rapid acting inhaled insulin suitable for patients with both type 1 & type 2 diabetes. This is to be taken before meals & it shows its effects as early as 15-20 minutes after administration. In patients with type 1 diabetes, it should be taken along with a long acting insulin.

External Insulin Pump

This is a battery-operated device. The insulin is loaded in a reservoir that is placed in a small plastic case. Insulin is released through a thin tube attached to a fine needle that is fixed under the skin. Depending on how you program, it controls the amount of insulin that is delivered to the body. It can deliver insulin throughout the day.

Most patients tie the case to their waist belt to make it convenient to insert the needle in their abdomen. The needle site must be changed a few inches every 3 to 4 days to prevent infection.

Administering Insulin

Step 1- Be ready with your insulin supplies

Sterile syringe

Insulin bottle

Alcohol wipes

Plastic container to dispose off injections

Check the expiry date of insulin

Ensure that there are no clumps or particles in the vial.

Step 2- Preparing the syringe

Remove the insulin vial cap.

Roll the bottle in between the palms. Don’t shake too vigorously

Keep the insulin bottle on a flat surface.

Remove cap from the needle, pull the plunger of the syringe and draw air.

Insert the needle into the vial and inject air. This helps in maintaining the right pressure in the vial and helps to draw out insulin easily.

Hold the syringe in place and now pull the plunger to draw insulin.

Remove the needle from the vial and make sure that the needle doesn’t touch any surface.

Step 3- Delivering insulin

Select the site of insulin delivery:

Insulin can be delivered at the areas with good muscle bulk. Its absorption is fastest in the abdomen, followed by the arms, thighs, and buttocks. Choose the spot that can be seen and reached well.

Clean the injection area:

Use alcohol wipes to clean the area where you plan to inject insulin.

Pinch the skin:

Pinch 1-2 inches of your skin between your thumb and the index finger

Stick the needle into your skin:

Hold the syringe (or the pen) at a 90-degree angle, insert the needle in one quick motion. Make sure that the needle is well inserted.

Administer insulin:

Let go off the pinched skin, slowly & firmly, push the plunger till all the insulin is into the muscle bulk.

Pull off the needle:

Remove the needle slowly while maintaining a 90-degree angle. After removing the needle, apply mild pressure on the injection site for 5-10 seconds.

Dispose the needle:

Do not put the cap back again on a used needle. Throw the entire needle and the syringe in a thick plastic container.

Rotating the injection sites:

Insulin injection is usually painless, but if this injection is administered repeatedly on the same site, there is inflammation and breakdown of the fat tissues. This is known as lipodystrophy. This causes swelling and thickened skin which impairs absorption of insulin. In order to prevent this, you must rotate the injection site.

Insulin should be injected at-least 1.5 inches away from the last injection site. This would make the insulin administration safer, comfortable and more effective.

Tips for storing insulin

  • Unopened insulin bottles can be kept at room temperature for a month.
  • The extra insulin bottles and related supplies can be stored in refrigerator till their expiration dates.
  • Once opened, insulin bottles should be refrigerated and used within one month.
  • Insulin should be refrigerated and stored at a temperature of around 36°F to 46°F.
  • Do not expose insulin to extreme temperatures, as it can result in decreased effectiveness of insulin.
  • Do not use the insulin that has been frozen. Insulin should always be at room temperature when used
  • Insulin vials can also be stored at room temperature for about a month.
  • The shelf life of the various insulin pens varies (between 10 days -1 month). Read the instruction manual that comes with your insulin device.
  • Never ever use the insulin past its expiration date.

Side effects of Insulin

As with any medication, insulin also has some side effects. The common side effects of insulin therapy are hypoglycemia (low blood glucose) and weight gain.

Hypoglycaemia

It is an emergency situation. If left untreated, it can lead to seizures, loss of consciousness and even coma. Hypoglycaemia occurs mainly due to vigorous physical activity, delaying or missing meals or taking too much of insulin.

Check the booklet on hypoglycaemia to understand its signs and treatment.

Weight gain

Another side effect of insulin is weight gain, which occurs after its prolonged usage. Your weight can be kept under check to some extent by following these tips:

  • Avoid food that contains high calories.
  • Do not skip meals.
  • Perform regular exercises.

Scars at the injection site

You might have scars or lumps at the areas where you have inserted the needle many times. Make sure you change the site of inserting the needle after every injection.

Dawn phenomenon

In some diabetics, there is an abnormal increase in the glucose early in the morning i.e between 2 am and 8 am. When you sleep, you don’t need much energy, but when you are about to wake up your body systems start generating glucose. In order to utilize this glucose, we also need more insulin. In diabetics, the insulin release or response is impaired, therefore when the body is preparing itself to wake up (morning 2 am to 6 am ), there is excess glucose in the blood and the body cells are not able to take them up.

Ways to reduce the impact of Dawn phenomenon:

Avoid eating high carb foods at night

Use an insulin pump overnight

Take insulin before bedtime

Ask the doctor if you need any change in the dose of insulin

Management of diabetes with insulin therapy can be a major challenge. Opt for a device that suits you the best to deliver insulin. You must meet your doctor regularly for dose adjustments, as the insulin levels frequently fluctuate.