Types of Insulins and Their Differences
Today, doctors have several dozen different insulin preparations at their disposal. All of them can be divided into 3 main groups (according to the duration of the effect and the time of its onset): fast-acting (short-acting), medium-acting and long-acting.
Fast-acting insulins - also called simple - are administered immediately before main meals: breakfast, lunch and dinner. These insulins are always clear. The therapeutic effect appears 15-30 minutes after the injection.
Maximum activity (or peak of action, peak of activity) occurs between 1.5-3 hours from the moment of administration. The duration of action (about 6-8 hours) depends on the dose of insulin: the greater the amount of simple insulin administered, the longer it works. Such insulins include actrapid, humulin-R, insulinrap, berlinsulin-N-nor-mal, homorapid, monosulin and others.
Medium- and long-acting drugs are administered 1-2 times a day. They are designed to maintain a certain level of insulin in the blood throughout the day, thereby replacing, as far as possible, basal insulin secretion.
Such insulins, on the contrary, are always cloudy. Turbidity is determined by the presence of special substances in them that slow down the absorption of insulin.
Intermediate-acting insulins constitute the largest group of drugs that differ in their basic characteristics from other insulins. They begin to act 1-2-3 hours after injection, have different peaks of activity: between 4 and 8 or 6 and 12 hours from injection, and the duration of action is from 10-16 hours to 18-24. These drugs include semilente, insulong, lente, monotard, protophan, actrafan, humulin-N, NPH-iletin-1, lente-iletin-1, lente-iletin-2, basal-insulin and others. Injections of these insulins are usually given 2 times a day.
Long-acting insulins begin to act after 4-6 hours, peak activity is between 14 and 22-24 hours, the total duration of action is 28-36 hours. These include ultratard, ultralente-iletin-1, huminsulin "lil-li" ultralong and others.
It should be noted that in reality the duration of action of insulins is less than indicated. Of course, we can find remnants of a long-acting drug in the blood both after 30 and 35 hours, but these are only traces, an inactive amount. That is why, to recreate the basic secretion of insulin, these drugs are administered not after 36, but after 24 hours. For the same reason, injections of intermediate-acting insulins are usually given twice a day.
Insulins differ not only in duration of action, but also in origin. There are animal and human insulins (more correctly, identical to human). Animal insulins are obtained from the pancreas of pigs and cattle. In its biological structure, pork insulin is closest to human insulin, which differs from it in only one amino acid.
Today, human insulins are considered the best drugs. Half of the patients who need injections are treated with them. Human insulins are produced in two ways.
The first is to “remake” pork, in which one amino acid is replaced. This is semi-synthetic human insulin. In the second method, using genetic engineering methods, “E. Coli” (Escherichia coli) is “forced” to synthesize insulin similar to human insulin.
The resulting drug is called biosynthetic human insulin. Human insulins have a number of advantages over drugs of animal origin: to achieve compensation they require smaller doses, the percentage of lipodystrophies is relatively small, and there are practically no allergic reactions.
Allergies when using animal insulins occur because they contain a foreign protein. Its quantity in the preparation depends on the quality of insulin purification during the manufacturing process.
In accordance with the method and degree of purification, insulins are divided into traditional,