Insulin is one of the important medicines used in the treatment of diabetes. It is prescribed for many people with diabetes and for patients with type I diabetes it is mandatory. If your doctor has prescribed you insulin, it becomes important for you to have some basic understanding of this medicine.
What does insulin do?
The purpose of the food we eat is to supply us with energy to perform various activities. The process starts with our digestive system breaking down the food particles into a simpler form called glucose. Glucose enters the blood stream from where it is taken inside the cells of the body to release energy. It is at this stage that insulin comes into picture. After the food gets digested, the level of glucose in the blood rises. In response to this, insulin is released from an organ called pancreas which is situated behind the stomach. Insulin helps the glucose to enter the cells and be used for energy production.
The process of utilization of glucose by the body is hampered in diabetes thereby, raising its level in the blood. In patients with type I diabetes, insulin is not produced at all and in type II, the produced insulin is either insufficient or the body develops resistance to it. In such circumstances, insulin has to be provided to the body, sometimes along with other oral glucose lowering medications.
Types of insulin
There are different types of insulin used in the treatment of diabetes. The types vary 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. Sometimes 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 |
|---|---|---|---|---|
| Rapid-acting | Within 15mins | 30mins to 3 hours | 2-5 hours | Can be taken right before eating |
| Short-acting | 30mins- 1 hour | 2-4 hours | 8 hours | Should be take 30mins before eating |
| Intermediate- acting | 1-4 hours | 4-12 hours | 12-18 hours | 30mins before eating. Often prescribed at bed time or twice a day |
| Long-acting | 1-10 hours | No clear peak time of action as it remains in a steady state throughout | 24hrs | Usually prescribed once or twice a day |
Taking Insulin Injections
Depending on your daily activity levels and other health conditions, your doctor will make a plan on the dose, type of insulin and how many times a day you should take insulin. Some patients require insulin two times a day while others require it 3 to 4 times a day. Though you might like to take insulin orally, unfortunately it is not possible. The digestive juices deactivates the insulin making it unfit for use.
You should take insulin before a meal. When exactly before a meal you should take insulin depends on the type of insulin and also your doctor’s advice. Be sure that you take insulin at the same time each day as advised.
Insulin should be injected just under the skin. There are several places where it can be injected. It works fast when it is injected near the stomach. It can also be injected in the arms, thighs or buttocks. When injected into the arm, it works at a comparatively slower speed than when injected near the stomach and still lower injected into the thighs or buttocks.
Depending on whether a single type or a combination of types is used, your doctor or the health educator will explain how to load the syringe with the required dose of insulin. After you have loaded the syringe, wipe the skin area where you want to prick, with cotton dipped in alcohol. Grab a fold of your skin and pierce the needle at 90- degrees and then push the insulin from the syringe into the skin. Once all the insulin is into the skin, remove the needle.
Pricking with the needle in the same place each time can cause thickening of the skin. So, rotate the place where you inject each time, giving time for the previous site to heal.
Devices that deliver insulin
Apart from the regular needle and syringe method, there are many insulin delivering devices available in the market. The most popular among them are: insulin pens, external insulin pump and insulin ports. You can select the one which is most convenient to you.
Insulin pens
Insulin pens cause less pain than the standard needle and syringe and are also easy to use. It looks like a pen with a cartridge attached. 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 the insulin.
External insulin pump
This is a battery operated device. It consists of a small plastic case which houses a reservoir into which insulin is loaded. From this, insulin comes through a thin tube to which is attached a fine needle. The needle is fixed under the skin. Most patients tie the case to their waist belt to make it convenient to insert the needle in their abdomen. You need to change the needle site a few inches every 3 to 4 days to prevent infection. Depending on how you programme, it controls the amount of glucose that is delivered to the body. It can deliver insulin throughout the day. If you are using this device, you should be able to do: continuous self-monitoring of glucose, determine doses, and program the device to deliver the required dose.
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 avoids you from pricking every day.
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.
Hypoglycemia
It is an emergency situation. If left untreated, it can lead to seizures, loss of consciousness and even coma. Hypoglycemia occurs mainly due to vigorous physical activity, delaying or missing meals or taking too much of insulin.
Common symptoms are:
- Tiredness of weakness
- Cold and clammy skin
- Paleness
- Haziness in vision
- Nervousness
- Excessive hunger
- Dizziness
- Confusion
- Drowsiness
- Irritable mood
If you experience any of these symptoms, you should immediately take a few spoons of glucose or table sugar or a glass of fruit juice. You will feel better within 10 to 15mins. Do not forget to inform your doctor about this reaction so that the dose of insulin can be adjusted to prevent these attacks in future.
Weight gain
The other common side effect with insulin is weight gain. This occurs with prolonged usage of insulin. Your weight can be kept under check to some extent by following these tips:
- Avoid food that contains high calories. The excess glucose they provide will be stored in the body tissue as fat increasing your weight.
- Do not skip meals
- Improve your physical activity
