Units of measurement are milligrams. “difficulty of translation” or the principle of dilution and calculation of peptide dosage. Recommendations for indicating dosage in the names of medicinal products

This is not the first time I have encountered a situation in which young peptide researchers are wondering about the dosage of a particular substance. There are a lot of opinions large number all kinds of calculators and a lot of hypotheses like “I swear on my mother.” But, as it turns out in fact, all this (swamp) does not stand up to criticism, both from the point of view of practical and economical application, and from the point of view of elementary mathematics. I generally remain silent about the “usefulness” of individual hypotheses.
So, let's figure it out.
The most important rule is that the amount of the active substance does not depend on the amount of liquid in which this substance will be dissolved. This can be illustrated at simple example. Imagine a glass of flour and a glass of water. If you mix them, you get a rather thick and sticky “solution”. If you continue to add water, the solution will become less and less thick. And finally, if you mix 3 liters of water with a glass of flour, we will get practically the same water, which does not have the density, thickness and “stickiness” that we observed when mixing one to one. Has the amount of flour changed? No (those who answered “yes” must re-read the previous sentences 20 more times)! When making a “solution” with both 1 glass of water and 3 liters of water, we sprinkled the same amount of flour - one glass.
Let’s now take our overworked brain into reality and imagine an ordinary bottle with five milligrams of the substance. By diluting these 5 mg of a substance, for example, 1 ml of liquid, we will obtain a solution in which there will be the same 5 mg of the substance. By diluting these 5 mg of the substance with 2 ml of liquid, we will also obtain a solution in which there will be 5 mg of the substance. What has changed (after all, a stressed-out brain still understands that something is wrong)? Concentration. The concentration of the active substance has changed. In 1 ml of liquid the concentration of the substance will be higher than in 2 ml.
Let's move on. How many micrograms are in 1 milligram? Whoever thought 1000 is well done. Why do we need this? In order to calculate the dosage. We know that the standard for calculating peptides for research is “1 mcg of a substance equals 1 kg of body weight.” But mcg is a unit of measurement for a dry (not liquid) substance, and research is only possible with a liquid solution, which is drawn up with an insulin syringe of 100 units. How do you convert these dry micrograms into liquid insulin units? To solve this puzzle, they use a liquid in which these dry micrograms are dissolved.
We remember that you can pour as much liquid as you like into the bottle, and the concentration changes. So, if we pour 1 ml of liquid into a bottle with 5 mg of a substance, we will get 1 ml of a solution in which there is 5000 mcg of a substance. Now look at the insulin syringe. There, 100 units are divided into 50 divisions and this entire economy is equal to 1 ml of liquid. We remember the standard 1 kg = 1 µg and understand that if we fill all 100 units (1 ml) of liquid solution into an insulin syringe, we will get a ratio of 5000 µg = 5000 kg. This is a little more than we need. But we need, for example, 100 mcg. Therefore, we need to draw 50 times less with a syringe. Those. We take out calculators and divide our 100 units (50 divisions) by 50. We get 2 units (1 division). In total, with a solution per 1 ml of liquid, 100 mcg is 2 units (1 division) of an insulin syringe per 100 units.
If anyone is comfortable conducting research with such proportions, they may not read further. But, if you don’t have the skills to pick up fleas and dealing with such small volumes is not for you, then you’ll have to read further.
As you might guess, the solution to the problem of more or less correct calculation and at the same time increasing visibility for the convenience of conducting research is to increase the volume of the solution without increasing the amount of the active substance. We remember: “the greater the amount of liquid, the lower the concentration of the active substance.” And thus add another 1 ml to the already “poured” 1 ml of liquid. We obtain a 2 ml solution of 5000 mcg of the substance. When converting this into units and dividing the insulin syringe by 100 units, we simply need to multiply everything by 2. Thus, per 100 kg we get 4 units (2 divisions) of solution.
Taking these serious mathematical calculations as a basis, we can calculate that in a solution with 2 ml of liquid and 5 mg of substance (each unit contains 25 mcg of peptide, each division contains 50 mcg of peptide) we get:
3 units correspond to 1.5 (about 2) divisions correspond to 80 kg
4 units correspond to 2 divisions correspond to 90 kg
4 units correspond to 2 divisions correspond to 100 kg
4 units correspond to 2 divisions correspond to 110 kg
5 units correspond to 2 divisions correspond to 120 kg
5 units correspond to 3 divisions correspond to 130 kg
6 units correspond to 3 divisions correspond to 140 kg
6 units correspond to 3 divisions correspond to 150 kg
As we can see, the 2 divisions correspond to a weight in the range from 80 to 120 kg. And this is not a mistake. The fact is that even with a solution of 2 ml of liquid, it is quite difficult to measure exact dosages with an insulin syringe of 100 units, so these small 2 divisions contain a range of 40 kg.
Let's try to figure out a bottle containing 2 mg of a substance and, accordingly, a solution of 2 ml of liquid (each unit contains 10 μg of peptide, each division contains 20 μg of peptide). We receive the following data:
4 units correspond to 2 divisions correspond to 40 kg
(but this is generally not enough, so let’s move straight to the equivalent of 80 kg)
8 units correspond to 4 divisions correspond to 80 kg
9 units correspond to 5 divisions correspond to 90 kg
10 units correspond to 5 divisions correspond to 100 kg
11 units correspond to 6 divisions correspond to 110 kg
12 units correspond to 6 divisions correspond to 120 kg
13 units correspond to 7 divisions correspond to 130 kg
14 units correspond to 7 divisions correspond to 140 kg
15 units correspond to 8 divisions correspond to 150 kg
It makes no sense to continue calculations with 10 mg of a substance and 2 ml of a solution, since substances contained in such quantities in one vial are used in studies based on other μg/kg ratios.
For researchers who in their “experiments” use not 2, but more ml of water (for example, 2.5 or 3), the proportions will look like this:
For 2.5 ml of water and 5 mg of peptide (each unit contains 20 μg of peptide, each division contains 40 μg of peptide):
3 units correspond to 1 division correspond to 50 kg
3 units correspond to 2 divisions correspond to 60 kg
4 units correspond to 2 divisions correspond to 70 kg
4 units correspond to 2 divisions correspond to 80 kg
5 units correspond to 2 (2.5) divisions correspond to 90 kg
5 units correspond to 3 divisions correspond to 100 kg
6 units correspond to 3 divisions correspond to 110 kg
6 units correspond to 3 divisions correspond to 120 kg
7 units correspond to 3 divisions correspond to 130 kg
7 units correspond to 4 divisions correspond to 140 kg
8 units correspond to 4 divisions correspond to 150 kg
For 2.5 ml water and 2 mg peptide (each unit contains 8 mcg of peptide, each division contains 16 mcg of peptide):
6 units correspond to 3 divisions correspond to 50 kg
8 units correspond to 4 divisions correspond to 60 kg
9 units correspond to 4 divisions correspond to 70 kg
10 units correspond to 5 divisions correspond to 80 kg
11 units correspond to 6 divisions correspond to 90 kg
13 units correspond to 6 divisions correspond to 100 kg
14 units correspond to 7 divisions correspond to 110 kg
15 units correspond to 8 divisions correspond to 120 kg
16 units correspond to 8 divisions correspond to 130 kg
18 units correspond to 9 divisions correspond to 140 kg
19 units correspond to 9 divisions correspond to 150 kg
For 3 ml of water and 5 mg of peptide (each unit contains 17 μg of peptide, each division contains 33 μg of peptide):
3 units correspond to 2 divisions correspond to 50 kg
4 units correspond to 2 divisions correspond to 60 kg

Typically, measures of volume and length are of interest to those who study the elementary laws of physics or where it is necessary to convert one unit of measurement to another. Let's consider important question physicists - a system for converting milligrams to milliliters and vice versa.

Definition of concepts

In accordance with the international classification of translation, a milligram means 1/1000 of a gram or 1/1000,000th of a kilogram.

It is a submultiple unit of mass measurement and cannot be the full equivalent of a milliliter due to the different volume and density of the substance. In international standardization it is designated as “mg”, while in Russia the abbreviation “mg” is accepted.

100 mg is 1/10 gram, but in relation to water, almost ten thousand times less than one liter. This fact is important to consider when using international system transfer from one unit of weight to another, but it is best to use special school cards. They allow you to repeat the translation table in time.

Translation rules

From a physics course we know that correct conversion from one unit of measurement to another is possible solely thanks to such a concept as the density of a substance. This also applies to the specifics of converting mg to ml.

Practice shows that 1 mg equal to one cubic centimeter. But the weight of liquid substances cannot be fully compared with the weight of solid substances. For example, the volume of a particular liquid depends on the density of the substance itself in the liquid state.

Density varies significantly depending on what material is used for analysis. All data for translation can be found from the standard tabular function, which is available in any school physics textbook.

To accurately carry out the translation (determine 5 ml - how many grams), you must follow the following steps:

Keep in mind that a milliliter does not always correspond to a milligram; the only exception is water, and then only approximately.
A gram divided by a cubic centimeter must be converted to a milligram, divided by millimeter cubed.
Keep in mind that some liquids can be much heavier ordinary water, for example: mercury and some other liquids.

If you want to find out how many milligrams are in a milliliter of a certain liquid, for example water.

We said above that the weight of water is comparable to the weight of a solid, which is explained by the density values. 1 ml of water is equal to a thousandth of one liter, just as 1 milligram is just a thousandth of a gram.

Density clean water – 0.997 kg per cubic meter . In order to answer the question of how to convert milligrams to milliliters, they resort to the standard system for converting units of measurement that are studied in high school.

To know how many mg are contained in a ml, it is important to understand the ratio of the tabulated parameters and strictly adhere to all data.

Important! Taking into account the values in ml or mg is necessary to determine and calculate the dose of the drug. In case of violation of established standard indicators, there is a high probability of causing harm to the patient’s health.

The table shows the main indicators medical meanings when transferring from one unit to another

From the table above it becomes clear and clear that the weight of liquid and dense matter does not always coincide. This is due to the different density and volume of the substance that needs to be converted into milliliters.

Advice! When calculating and converting one unit of measurement, it is advisable to follow strict tabular values. This will help to avoid many problems with solving a physical or chemical problem.

What is larger - milligram or milliliter?- now you know. It is easy to understand that one liter is not always equal to a kilogram, even if we do not neglect some other physical indicators.

Using the calculator

No need to use it today hand tools for accurate calculation of values. It is most practical to use a adding machine. Automatic calculation makes it possible to find out how many mg are in a milliliter of water, since a milligram and a milliliter of water are different quantities.

The difference is often life-changing. That is why using a calculator makes it possible get rid of many problems. This situation has been proven by leading scientists and ordinary schoolchildren.

We need to determine what 1 gram of mercury is equal to. Not every student knows that mercury is the heaviest liquid.

The difference with gasoline exceeds 19 integer values. The metric table makes this clear.

The ratio of tenths of grams to ml is determined by a number of factors. Here are the most common of them:

the need to adhere to the values of derivatives in the SI system;
pay attention to examples of physical quantities;
realize that 1 mg is one millionth of a kilogram;
accounting specific gravity as a basic physical quantity; it shows how many grams it is;
the presence of strong or weak solutions when measuring the product.

If you take 1 kilogram of a liquid or 1 kilogram of a solid, not all students give the correct answer to the question.

We already talked above about how to determine how many milligrams are in a ml of water, as well as what the ratio mg and ml in substance. From now on, everyone who reads this article knows what or what value 1 mg of water is equal to without taking into account impurities.

From arithmetic we know that 1 g is a multiple of 1 kg, that is, a thousandth of a kilogram. And when you need to find out how many grams are in a kilogram, we multiply the number denoting kilograms by a thousand and get:
1 kg x 1000 = 1000 g, or 1 kg = 103 g.

So, a milligram is also a thousandth of a value called a gram.

And the problem is solved in a similar way when you need to find out how many milligrams are in it.
We assign three zeros to the number that denotes the amount of g.

1 g x 1000 = 1000 mg, or 1 g = 103 mg. Here is a simple answer to the question - how many mg are in 1 gram?

Putting knowledge into practice

Life constantly confronts us with a situation where we have to solve similar arithmetic problems. Most often, this occurs when taking medications.

For example, if the instructions for use say that you should not take more than 0.2 g of the drug per day, and the tablets in the blister indicate the weight of 25 mg, then you need to find out how many tablets you can use.

Solution algorithm: 0.2 g x1000=200 mg, 200 mg:25 mg=8 tablets.

But the reverse conversion from milligrams to grams is also often found, especially when preparing food or for chemical solutions for household purposes.

We remember that if 1 g = 103 mg, then 1 mg = 10-3 g or 1 mg = 0.001 g.
Suppose, according to the recipe, we need to add 300 mg of granulated sugar and 800 mg of salt somewhere, and our scales only measure g.

International unit (IU)- in pharmacology, a unit of measurement of the amount of a substance based on biological activity. Used for vitamins, hormones, some drugs, vaccines, blood components and similar biologically active substances.

How many milligrams are in a gram?

Despite its name, IU is not part of the international measurement system SI.

The precise definition of a single IU varies for different substances and is established by international agreement. The World Health Organization's Biological Standardization Committee provides reference materials for certain substances, (arbitrarily) specifies the number of IUs they contain, and defines biological procedures for comparing other materials with the standards. The goal of such procedures is to ensure that different preparations having the same biological activity contain equal numbers of IU units.

For some substances, mass equivalents of one IU were eventually established, and measurement in these units was officially abandoned. However, the IU unit may still remain in widespread use because of convenience. For example, vitamin E exists in eight different forms, differing in their biological activity. Instead of accurately indicating the type and mass of the vitamin in the preparation, sometimes it is convenient to simply indicate its quantity in IU.

Wikipedia

International unit (IU)— internationally agreed standards necessary to compare the content of different test biological compounds on the basis of their activity.

If cleaning is not possible chemical methods the substance is analyzed by biological methods, and a stable standard solution is used for comparison. Serum standards are stored in State Institute serum (Copenhagen, Denmark), at the National Institute for Health Research (Mill Hill, UK) and at the World Health Organization (WHO) (Geneva, Switzerland).

International unit established in the form of a certain amount of standard solution (for example, one IU of tetanus antitoxin = 0.1547 mg of standard solution, which is stored in Copenhagen).

Pharmacology And Pharmacotherapeutics (New Revised 21 St Ed.)

How much is 5 milligrams?

What is the difference between 5 mg and 5 ml?

People quite often confuse two completely different concepts: milliliter and milligram. Some people think they are the same thing. So let's figure it out.

To begin with, you need to determine which dosage form in front of us.

Solids are dosed by mass (weighed), and liquids are dosed by volume (measured).

In the first case, the unit of measurement is gram\milligram\microgram, and in the second - liter\milliliter.

Dosing by weight

Weight designations :

1.0 - 1 g (gram)

0.001 - 1 mg (milligram)

0.000001 - 1 mcg (microgram)

Measuring weights, weights, scales (based on the principle of weighing there are: spring, lever, manual, plate and others).

Measuring tools for the consumer: The measure of measurement in this case will be the dosage of the drug prescribed by the doctor. We talked about dosages in more detail in article.

Dosing by volume

Volume designations:

1 ml - 1 milliliter

1 l - 1 liter

MeasuringTools for the manufacturer: measuring and pharmaceutical pipettes, volumetric flasks, cylinders, beakers, burettes.

Measuring tools for the consumer: caps, pipettes, syringes, cups, measuring spoons.

Let's fix:

What does the designation say? 1,0 ?

Answer: This is the mass of a substance weighing 1 gram.

Clarification: If we are talking about the volume of the dosage form, then next to it there will be a designation - ml, that is 1.0 ml(or just 1 ml).

How to calculate the required number of drops?

A non-standard unit of measurement for volume is drop.

How many milligrams are in 1 gram?

This is an inaccurate indicator for calculations, because the volume of the drop depends on the physical properties of the dosed liquid.

For comparison: the volume of 1 drop of an alcohol solution is on average 0.02 ml, while that of an aqueous solution can range from 0.03 to 0.05 ml.

Pharmacists and doctors decided to jointly designate a standard measure for this unit of measurement. It is generally accepted that the volume of 1 drop is 0.05 ml.

When the dosage of a drug in drops is prescribed, it is assumed that the volume of one drop is 0.05 ml. If you have a 1 ml medical syringe at home, then you can easily determine the required volume of medicine: 2 drops - 0.1 ml, 3 drops - 0.15 ml, 5 drops - 0.25 ml.

Spoons are also inaccurate measuring instrument to determine the volume of the dosage form. Volume conventions are also adopted for them.

Reminder when dosing liquid dosage forms:

1 drop (drop) = 0.05 ml

2 drops = 0.1 ml (measured with a 1 ml syringe)

20 drops (pipette) = 1 ml

1 tsp (teaspoon) = 5 ml

1 d.l. (dessert or baby spoon) =10 ml

1 tbsp. (tablespoon) = 15 ml

1 tbsp. (glass) = on average 200 ml (glasses come in different capacities: from 110 to 320 ml)

In one of the following issues, you will learn how to determine the content of the active substance in the dosage form, and how to calculate single/daily doses of the drug.

Be healthy! Treat consciously!

#CaringPharmacist

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Quick answer: 1 g - 1000 mg.

Whatever you say, we tend to forget some information from school, especially if we never encounter it throughout our lives. For example, do you remember how many milligrams are contained in 1 gram?

How many milligrams are in one gram?

It’s good if you remember, but there are people who have forgotten this information. Let's not blame them - a person is not able to store in his head all the data that he once received. But we will answer the question.

A milligram is a unit of mass in the International System of Units (SI). A milligram is one thousandth of a gram (or one millionth of a kilogram). It turns out that 1 g of the substance contains 1000 mg. 1 milligram, in turn, contains 0.001 g of the substance.

Is it easy to remember?

Quite. However, in practice, we often encounter cases that often lead us into a stupor. A simple example: you need to take a pill. The packaging says that the weight of each tablet is 0.25 g, while you need to take 750 mg. Since we already know that one gram contains a thousand milligrams, we will simply convert the values. So, 0.25 g is 250 mg. We divide the prescribed 750 mg by 250 mg and get the number 3. Three - that’s exactly how many tablets you need to take.

Of course, you can translate everything back. 750 mg is 0.75 g. A tablet weighs 0.25 g. Divide 0.75 g by 0.25 g and get the same figure - 3. As you can see, everything is quite easy and simple, but if you have any questions on this topic, you can ask them to us using the comment section.

When working with small quantities of a substance, the unit of mass used is often the milligram (mg). A milligram is a thousandth of a gram. that is, one gram contains one thousand milligrams. To convert grams to milligrams you don’t even need a calculator – just basic knowledge of arithmetic.

Instructions

1. To convert a gram to a milligram, multiply the number of grams by 1000. That is, use the following primitive formula: Kmg = Kg * 1000, where Kmg is the number of milligrams, Kg is the number of grams. So, say, the mass of one tablet of activated carbon is 0.25 grams. Consequently, its mass, expressed in milligrams, will be: 0.25*1000=250 (mg).

2. If the number grams is an integer, then to convert grams to milligrams, simply add three zeros to the right of it. Let's say one tablet of ascorbic acid with glucose weighs 1 gram. This means its mass in milligrams will be: 1,000.

3. If the number of grams is expressed in the form decimal, then move the decimal point three digits to the right. Let's say the content of glucose in one tablet of ascorbic acid with glucose is 0.887 grams. Consequently, in milligrams the mass of glucose will be 887 mg.

4. If there are less than 3 digits after the comma, complete the missing characters with zeros. So, say, the table of contents of ascorbic acid in one tablet of ascorbic acid with glucose is 0.1 grams. In milligrams it will be 100 mg (according to the rule, it turns out to be 0100 mg, but insignificant zeros on the left are discarded)..

5. If all the initial data are given in grams, and the result needs to be presented in milligrams, then carry out all intermediate calculations in grams, and convert only the result of the calculations into milligrams. So, let’s say, one tablet of allochol contains: - dry bile – 0.08 g - garlic dried – 0.04 g - nettle leaves – 0.005 g, - coal activated - 0.025 g. In order to calculate how many milligrams of energetic substances are contained in one allochol tablet, add up the masses of all components, expressed in grams, and convert the result into milligrams: 0.08 + 0.04 + 0.005 + 0.025 = 0.15 (g ).0.15*1000=150 (mg).

Gram is a unit of measurement of mass belonging to the metric system. Gram is one of the basic units of the GHS system of unconditional measures (centimeter, gram, second) - widely used before the adoption of the International System of Measurement (SI). Denoted as g or g.

How many milligrams are in one milliliter?

Its multiple unit of measurement of mass kilogram is one of the basic SI units, denoted kg or kg.

Instructions

1. Gram equal to the mass of one cubic centimeter of water at the temperature of its maximum density (4°C). As a measure of body mass, the gram is a derived unit in the metric system. It is one thousandth of the rod unit of mass - kilogram A. A kilogram was defined (with an accuracy of 0.2%) as the mass of one cubic decimeter (0.001 cubic meter) of water at the temperature of its highest density. Currently, to determine mass kilogram and the International Bureau of Weights and Measures in Paris maintains the standard kilogram a is a cylinder about 39 mm high, produced from a platinum-iridium alloy in 1889.

2. Gram equal to one thousandth kilogram a (1 g = 0.001 kg), therefore, to convert the known body weight, which is given in grams, you need to multiply it by 1000.

Video on the topic

Pay attention!
The conversion of grams to milligrams is used mainly in calculations related to the preparation of drugs and their dosage. When making calculations, be very careful - a mistake of one decimal place will lead to a tenfold error.

Much of what you read below may seem strange and even offensive. After all, this “much” is studied in the first three grades of a regular high school.

But still, reminders and primitive explanations can be useful, taking into account the fact that you will be doing the calculations in a particularly nervous state due to the child’s illness...

So, we will talk about how to correctly calculate the dose of medication for a child.

The dose of your child's prescribed medication should be measured in some way, and can be used as units of measurement :

units of mass (gram, milligram, etc.);
units of volume (liter, milliliter, drop, etc.);
special units (conditional, biological, etc.);
units of a specific dosage form (tablet, capsule, ampoule, etc.).

The basic unit of measurement for mass is gram and its derivatives - milligram and microgram.

Common abbreviations:

gram - g;
milligram - mg;
microgram - mcg.

In 1 g - 1,000 mg or 1,000,000 mcg.
1 mg contains 1,000 mcg.

1.0 is a gram;
0.001 is a milligram;
0.000001 is a microgram.

The basic unit of volume is milliliter . The usual liter in everyday life is rarely used as a dose, but still sometimes used. For example, “the volume of liquid required for a cleansing enema is 1 liter” or “the daily volume of infusion therapy is 1.5 liters.”

Common abbreviations:

liter - l;
milliliter - ml.

In 1 l - 1,000 ml.

The unit of volume must be indicated!

If it is not indicated, i.e. it is simply written 15.0, it means that this is not a volume, but a mass - 15 grams. If we are talking about milliliters, then next to the number 15 it should be written - ml: 15.0 ml.

Please be careful: The most common parental mistake is when they get confused MG And ML.

Let us draw your attention once again, since this particular point is extremely relevant!

Do not confuse units of mass and units of volume - this is very, very important!

Whenever a drug is prescribed parenterally in a certain number of ml, we are talking about the fact that this volume will be measured with an injection syringe of the appropriate size or an infusion solution bottle with appropriate volume marks will be used.

Modern packaging, dosed in milliliters medicines For reception inside must contain special measuring devices: caps, pipettes, syringes, cups, measuring spoons.

If there is nothing of the kind, but the medicine is still prescribed inside and in ml, which means that to measure the required volume, you should use injection syringes or special graduated measuring cups sold in pharmacies.

A non-standard and imprecise unit of volume measurement is drop . The volume of a drop is largely determined physical properties dosed liquid.

So, for example, the volume of one drop alcohol the solution is on average 0.02 ml, and the volume of one drop water solution can range from 0.03 to 0.05 ml.

Pharmacists and doctors have long agreed that The standard pharmaceutical, medical drop measure is 0.05 ml.

Thus, 1 ml = 20 drops.

When a solution of a particular drug is prescribed to your child in drops and we are talking about a modern medicine, the packaging usually contains a special pipette or the bottle cap is a special dropper.

If there is no pipette or dropper cap, then you can use a standard medical pipette sold in any pharmacy. If many drops are prescribed, it is quite possible to use a disposable syringe to measure the required volume of liquid.

Prescribed 10 drops - that means 0.5 ml; 40 drops - respectively, 2 ml.

You can even use the formula:

number of ml = number of drops divided by 20.

The main thing to remember is that whenever a certain medicine is prescribed in drops, and you cannot figure out how to extract and measure these drops, in such situations it is clearly understood that the volume of one drop is 0.05 ml. And this means that if you have a 1 ml medical syringe in your home, you can easily and absolutely accurately determine the required volume of medicine: 2 drops - 0.1 ml, 3 drops - 0.15 ml, 5 drops - 0.25 ml etc.

Even more non-standard (compared to drops) units of volume measurement are the various household spoons, which are sometimes (but less and less often) used for dosing low-active and relatively safe drugs.

Standard volume of spoons in ml:

tea room spoon - 5 ml;
dessert spoon - approximately 10 ml (there is no single standard);
dining room spoon - in the CIS countries - 18 ml, in the USA, Canada - 15 ml, in Australia - 20 ml;

In some countries, the concept of a baby spoon is used.

children's spoon - 10 ml.

To completely close the topic of kitchen utensils for measuring volume, let’s remember glass . Dosing with glasses is more common in cooking, but is sometimes used in medicine to measure the volume of infusions, decoctions, rinses, etc.

one glass - 200 ml.

The active substance is present in the liquid medicine in a certain concentration. The digital value of this concentration is reflected in such a seemingly obvious, but not always understandable expression as percentage of solution .

The expression “5% ascorbic acid solution” does not look complicated or mysterious at all. But still, some clarifications should be given in order to finally dot the i’s.

So, concentration in pharmacology is usually displayed as number of units of mass per unit of volume. Thus, the expression “1% solution” means that 100 ml of liquid contains 1 g of active substance.

In the vast majority of cases, the volume of fluid prescribed to the child is measured in milliliters. Therefore, we recalculate:
100 ml - 1 g;
10 ml - 0.1 g;
1 ml - 0.01 g.
0.01 g is 10 mg. A completely logical conclusion: at 1 ml of 1% solution contains 10 mg of active ingredient .

We train:

in 1 ml of 5% ascorbic acid solution - 50 mg of ascorbic acid;
in 1 ml of 50% analgin solution - 500 mg of analgin;
in 1 ml of 0.1% solution of loratadine - 1 mg of loratadine;
in 1 ml of 66.7% lactulose solution - 667 mg of lactulose;
in 1 ml of 0.05% chlorhexidine solution - 0.5 mg of chlorhexidine...

Manufacturers of children's dosage forms are very skeptical about parents' mathematical abilities. The instructions may well say “loratadine solution 0.1%,” but the packaging will indicate in large letters: “loratadine 1 mg/1 ml” or “loratadine 5 mg/5 ml.”

A huge number of liquid medicines are available in different concentrations. 1 ml of paracetamol suspension can contain 20, or maybe 50 mg: on the box with the suspension they will write “120 mg/5 ml” or “250 mg/5 ml”. The pharmacy worker will not be able to dispense it correctly, and the mother will not be able to correctly give the child paracetamol prescribed in a dose of “5 ml suspension” - you need to know what concentration of the suspension we are talking about. Thus, Whenever your child is prescribed anything liquid, it is important to make sure that you know not only the name of the solution, but also its concentration!

A situation where a doctor prescribes a solution, syrup, suspension, etc., but does not indicate the concentration, is nevertheless possible.

For example, lactulose syrups are produced by almost all manufacturers in the form of a 66.7% solution. And when the doctor wrote: “ Lactulose syrup 5 ml in the morning before breakfast", then there is no mistake in this.

Another option: we are talking about a drug prescribed under a specific trade name.

An example of such an assignment: “ Nurofen for children, suspension, at temperatures above 39 °C 10 ml orally" The suspension called “Nurofen for children” is available in only one concentration - 100 mg/5 ml. Therefore, everything is written correctly, it is impossible to make a mistake.

Another question is that the pharmacy may tell you something like this: “We currently do not have Nurofen for children in suspension. We have another medicine, but it contains ibuprofen, as well as nurofen, and this is different - only in tablets of 0.4. Everything else is in the regional center, the bus is tomorrow morning...”

And then you calculate:

10 ml with a concentration of 100 mg/5 ml - this means we were prescribed 200 mg.

And in a tablet 0.4 is 400 mg.

So, we will persuade Mashenka to swallow half a tablet...

Another fundamental important point. Knowing the concentration is necessary not only when drugs are taken orally and dosed in ml. For topical use and dosing with drops, this is no less important.

And if it is appointed " xylometazoline 2drops in each nostril 3once a day“, then before dripping, you should definitely clarify which xylometazoline we are talking about - 0.1% or 0.05%?

The concentration of the active substance in dermatological products is also indicated as a percentage, but there is no specificity here. Therefore, if it is written “ hydrocortisone ointment 1% ", this means that 1 ml of this ointment contains 10 mg of hydrocortisone. But just like with a paracetamol suspension, you cannot simply write “hydrocortisone ointment”, since this ointment comes in 0.5%, 1%, 2.5%...

Now about dosing using special units . Whenever we are talking about certain medicinal units, the number of these units is linked either to a unit of volume, or to a specific package or dosage form. And this relationship must be clarified!

That is, you must definitely know that in 1 ml of solution insulin contains exactly 40 units or exactly 100 units of the drug.

You definitely need to know what exactly is in this tablet with pancreatin contains a dose equal to 10,000 units of lipase. Exactly 10 thousand, not 40 or 25.

You must know that this particular sterile vial contains 500,000 units of sodium salt benzylpenicillin.

Once again I would like to emphasize that Whenever something is prescribed in units, it is imperative to clarify in what volume, in which bottle, in which capsule exactly this number of units is contained.

There are enormous difficulties and many errors associated with using the name of a specific dosage form as a dosage unit.

One tablet of the same pharmaceutical product may contain different quantities active substance. So, for example, in one tablet paracetamol may be 80, 120, 125, 200, 285, 325, 500 or 564 mg. Obviously, no one can correctly sell in a pharmacy or give a child paracetamol prescribed in a dose of “1 tablet”.

Therefore, next to the name of the drug and the selected dosage form, the amount of the active substance in this particular dosage form prescribed for a specific patient should be indicated.

Examples:

calcium gluconate, tablets 0.5;
cephalexin, capsules 0.25.

An indication of a certain tablet or capsule, in the absence of information about the content of the active substance, may in some cases be justified by the fact that there is no choice of tablets for this particular medication No.

This is possible if:

the drug is produced in this dosage form only with a strictly defined amount of the active substance. For example, ornidazole Available in tablets of 0.5. There are no other tablets. You can't go wrong;
the drug is prescribed under a trade name, and a specific manufacturer produces it only in this dosage form - there is no choice. For example, one tablet suprastina always contains 0.025 chloropyramine. Therefore, if Suprastin is prescribed one tablet twice a day, you can’t go wrong;
the drug is a strictly defined combination of certain ingredients protected by a trade name. For example, decathylene, lozenges. There is no other decathylene. You can't go wrong.

We already know that the optimal way to dose medications for children is based on the relationship between the dose and the child's weight.

Let's look at the subtleties of such dosing using the example of the most popular children's antipyretic drug - paracetamol.

From paragraph 2.1. we know that single dose paracetamol is 10-15 mg/kg.

We have a child weighing 15 kg. Thus, a single dose of the drug ranges from 150 (10 x 15) to 225 (15 x 15) mg.

We bought a 120 mg/5 ml suspension. This means in one ml - 24 mg. And we need from 150 to 225. This means that our single dose is approximately 6.2-9.3 ml.

We bought a 250 mg/5 ml suspension. This means 50 mg in one ml. And we need from 150 to 225. This means that our single dose is 3-4.5 ml.

We bought 200 mg tablets. And we need from 150 to 225. This means our single dose is 1 tablet.

We bought 325 mg tablets. And we need from 150 to 225. This means that our single dose is half a tablet.

Now let's deal with daily dose the same paracetamol. If indicated, this medicine can be given repeatedly during the day, but no more than 4-5 times, and it is very important that the interval between doses is at least 4 hours.

Still the same child - body weight 15 kg. Maximum daily dose In no case should the dose exceed 60 mg/kg. This means that our baby can take no more than 15 x 60 - 900 mg per day.

We bought a 120 mg/5 ml suspension. This means in one ml - 24 mg. And we need no more than 900. This means that our maximum daily dose is 37.5 ml (900/24).

We bought a 250 mg/5 ml suspension. This means 50 mg in one ml. And we need a maximum of 900 per day. This means that our daily dose should not exceed 18 ml (900/50).

We bought 200 mg tablets. This means you can’t take more than four tablets per day.

We bought 325 mg tablets. This means that our maximum daily dose is 2 tablets and another three-quarters of a tablet.

This list of ours already shows that, knowing the weight and the required single/daily dose, it is quite easy to make a rational choice of dosage form. Obviously, giving a child 3 ml of suspension in most cases is much easier than 10 ml or half a tablet. Therefore, for a child weighing 15 kg, the optimal dosage form of paracetamol would probably be a suspension of 250/5 ml.

Even more indicative in this aspect is the choice of the optimal dose of paracetamol for rectal administration.

It is known that when using suppositories, a single dose of paracetamol is higher than when taken orally, and is 20-25 mg/kg. Thus, a child weighing 10 kg should receive a suppository containing 200 to 250 mg. We go to the pharmacy, and it turns out that suppositories with paracetamol are available for sale, containing the active substance in quantities of 50, 80, 100, 125, 150, 250, 300, 500, 600 and even 1,000 mg. In our situation, it is most logical to buy 250 mg suppositories and use them with minimal stress on the child’s psyche. But you can not know all this and mock your child by putting two 100 mg suppositories into him, or mock yourself by trying to cut off half of a 500 mg suppository.

We also draw your attention to the fact that careful study of the sheet with medical prescriptions in many cases will allow you to save significant money.

Example of assignments: " azithromycin suspension. 200 mg 1 once a day half an hour before meals, 3 days in a row" We go to the pharmacy, and there it turns out that the antibiotic azithromycin in suspension is sold in the following packages:

powder for suspension 100 mg/5 ml, bottle 20 ml;
powder for suspension 200 mg/5 ml, bottle 15 ml;
powder for suspension 200 mg/5 ml, bottle 30 ml;
powder for suspension 200 mg/5 ml, bottle 20 ml.

It is clear that the optimal choice in our situation is 200 mg/5 ml, a 15 ml bottle - this is just enough for the prescribed course of treatment. Any other packaging is not economically profitable: you will either have to buy more or you will have to leave it.

Unfortunately, a situation often occurs when a doctor simply does not have time to keep up with the rapidly changing assortment of pharmacies. And in this case, the following assignments are quite possible: “ loratadine 5 mg 1once a day for 2weeks" This, of course, is wrong, but a very minor parental intellectual effort can solve the problem.

So, we come to the pharmacy. - I need loratadine, 5 mg.

It turns out that loratadine comes in 10 mg tablets, as well as in syrups or suspensions - 1 mg/1 ml.

5 mg is half a tablet or 5 ml of syrup. We don’t want to share pills, and our little one has problems swallowing pills, so we buy a tasty liquid and give it what the doctor prescribed...

By the way, before purchasing, we carry out simple calculations: 5 ml per day, and for 2 weeks, that’s 5 x 14 - it turns out that you need 70 ml for a course of treatment. How much is there in the bottle? We are interested: it turns out that one bottle of loratadine syrup or suspension can contain 30, 50, 60, 100, 120 and 150 ml. Probably the most rational way is to buy a 100 ml bottle - please give me...

And the last thing I would like to draw your attention to. Whenever a doctor prescribes dividing tablets, this is either indicated by the words (half, third, quarter) or by a fraction: 1/2, 1/3, 1/4.

And if it says “calcium gluconate 0.5” - this is not half a tablet (!), this is half a gram - 0.5 g.

0.25 is not a quarter of a tablet, it is 0.25 g.

Here and further, when we pronounce the expression “basic unit,” we mean the unit main from the standpoint of drug dosing. That is, we know that from the point of view of the international system of units (System International, SI), the basic unit of mass is the kilogram (kg), and the standard unit of volume is the cubic meter (m 3).

When we finish our studies, we often forget a lot of what we went through in the program. For example, not everyone remembers how many milligrams are in a gram. However, this knowledge is sometimes simply necessary in everyday life. For example, the correct dosage of various components in cooking, medicine, and cosmetology often depends on how well we have mastered the system for converting weight from kilograms to grams, from grams to milligrams. If you take this lightly, you can easily ruin the result. After all, it is much easier to figure out how much to add and where, knowing how many milligrams are in a gram. Small values are often used when working with small volumes of substances, and it is very important not to confuse the ratio. Even on the Internet, you can sometimes come across statements that confidently say that a gram contains 100 milligrams. But it is quite possible that, after reading such a post, another person will simply make a mistake with his calculations. So, how many milligrams are in a gram? And how to do the calculations correctly?

A milligram is a thousandth of a gram. The value of the prefix "milli" means 10 to the -3 power, respectively, indicating one thousandth. That is, one gram consists of one thousand milligrams. In fact, it is not at all difficult to convert these values even without a calculator. To do this, it is enough to use the most basic knowledge of arithmetic.

To make it easier to understand how many milligrams are in 1 gram, I will present a clear example:

1 gram is equal to 1,000 milligrams

And vice versa:

1 milligram is equal to 0.001 grams

It follows from this that:

1 kilogram is equal to 1,000 grams, which is equal to 1,000,000 milligrams

Using such a simple table, you can correctly calculate the amount of substances.

Knowing how many milligrams are in one gram is necessary if you want to correctly follow various recipes. cosmetics, medicines. After all, situations often arise when we can independently understand all the subtleties and nuances, but ignorance of how many milligrams are in a gram and well-founded uncertainty about the correctness of the calculations prevents us from finding a rational solution.

Suppose you need to give medicine small child. But it is known that the dosage of some drugs differs quite strictly between adults and children. In this case, the most difficult thing is to select the necessary dose that will not cause any side effects and negative effects on health for very young children under three years of age. Having a whole tablet and knowing its standard weight, as well as the amount of active substance, you can easily do this. In an example it looks like this.

Tablet weight is 500 milligrams. The pediatric dose of this drug is 0.25 grams. Difficult? Not at all. One has only to use the elementary school formula and everything will fall into place. You can use two in various ways converting quantities - from grams to milligrams or vice versa. This is what the result will be:

500 milligrams = 0.5 grams. And you only need 0.25. We divide the tablet into two parts and get the required dose of the required medicine.

You can do the other way around:

0.25 grams = 250 milligrams

The result is two numbers - 500 milligrams and 250 milligrams. And now it is much easier to understand how to properly split the tablet.

I will give a few more examples of converting grams to milligrams and vice versa.

0.12 grams = 120 milligrams.

540 milligrams = 0.54 grams

0.03 grams = 30 milligrams

36 milligrams = 0.036 grams

Here's how you can easily deal with such incomprehensible quantities. There is no need to divide or multiply if you correctly understand the number of zeros. In the version with 540 milligrams, 0.54 grams can be obtained by simply moving the separating comma three digits forward, which means three zeros in 1000. After all, did you remember that there are 1000 milligrams in one gram? And in the case of converting 0.03 grams to milligrams, the comma is moved back three digits and the missing zero is added. 0.030 = 30.