Insulin is a natural hormone produced by the pancreas and helps to control the use of glucose in the body. A child with diabetes is producing inadequate amounts of insulin, so we must replace the deficit with insulin given by injection.
Insulin is given once or several times a day Although your child may have to receive several injections a day when he is being ‘stabilized’ after he has first been diagnosed, it will be possible eventually to control the diabetes with one or two injections a day. This has been made possible by the development of modified types of insulin which have been produced by laboratory research, particularly in Scandinavia. The type of insulin that is likely to be most suitable for your child will be selected by his doctor. After a period of stabilization the dose required to keep him in good health will also be determined.
There are many insulin types and names and this can be confusing. Sometimes it turns out that it is hard to achieve good control on one type of insulin. Then it is possible to mix two insulins, or split the dose to two (or more) parts during the day. Occasionally your doctor may decide that a different type of insulin is worth trying. In all events, different people respond to insulin in somewhat different ways and it is sometimes a matter of trying one insulin and altering it if it doesn’t prove entirely satisfactory.
There are different types of insulin
You may wish to know about the different types of insulin and why there are several brands. This is partly due to the different processes used to make the insulin, and partly due to the fact that there are several insulin manufacturers each with their own brand.
In the past, there were two major ways that insulins differed from each other:
1. The animal species from which the insulin was derived;
2. The way in which insulin had been modified to change its time of action.
Insulin may be beef, pork, ‘human’
In the past almost all insulins were made either from beef or pork pancreas. Both worked perfectly well, but each insulin was a little different in its chemical composition to each other and to insulin made in the human body. Some few people have developed allergies or resistance to insulins derived from beef or pork, and all people developed some antibodies to animal insulin.
It is now possible to make insulin identical with human insulin. This should have the advantage that antibodies would not be formed. ‘Human’ insulin is not made from human pancreas of course.
It is made in the laboratory by a process of genetic engineering. In this process, simple yeast cells or bacterial cells have had their gene structure changed so they make human insulin in a similar way to the way pancreas cells make insulin in the human body. The altered bacterial or yeast cells can make large quantities of insulin commercially in a way that human pancreas cells cannot.
Insulin may be modified chemically to make it work more slowly
Insulin, as it is produced in the body, has a very rapid effect once it enters the blood stream. This effect wears off very quickly. This is what is required if the body is making it normally. It is also suitable for the person with diabetes who is given insulin continuously by slow injection or at short and frequent intervals during the day before meals. Most people find it more convenient, however, to have one or two injections a day rather than injections each time they have a meal. To do this, it is necessary to alter the insulin so that it has a prolonged effect.
Insulin manufacturers have developed methods of prolonging the effects of insulin by chemical processes that modify insulin. This may involve adding the metal zinc and a protein to the insulin which slow down its absorption into the bloodstream. You can usually recognize these modified insulins because they are a cloudy suspension while the unmodified quick insulins are clear solutions. Insulins therefore can be in one of several groups.
1. Fast acting, unmodified clear soluble solutions.
2. Slow acting modified insulins which may last up to 24 hours,
3. Intermediate acting modified insulins which last between 8 and 24 hours.
4. A mixture of slow or intermediate insulins and fast insulins.