Iron preparations for anemia: which are better absorbed

The human body contains various microelements – and one of them is iron. Its influence on most of the most important processes in the body is truly enormous. But the deficiency of this element immediately affects a person’s well-being, which can cause a lot of negative consequences – for example, anemia develops. Why is iron so important for anemia? Is it necessary to take iron supplements in all cases of anemia?

Treatment of anemia with iron

Iron performs many tasks in the body. The basic directions are considered to be the following:

• Oxygen delivery.

Iron is an important component of hemoglobin (a protein that makes up red blood cells), responsible for transporting oxygen to all tissues in the body. Blood cells, using the same iron, remove the produced carbon dioxide and transport it to the respiratory organs for removal. Therefore, the microelement we are considering plays an important role in all respiratory processes.

• Providing metabolic processes.

Iron is a part of most enzymes and proteins necessary for high-quality metabolism – for the removal of toxins, stable cholesterol balance, energy transformation. The immune system also depends on the presence of this element.

In a state of iron deficiency, the condition of the skin, hair, and nails worsens. Severe weakness, shortness of breath, drowsiness, irritability occur, and memory processes are disrupted.

According to statistics kept by the World Health Organization, 60% of the world's population has iron deficiency. Moreover, in half of them, this deficiency is so pronounced that doctors make a confident diagnosis of "iron deficiency anemia". This is a pathology that is accompanied by a significant decrease in hemoglobin levels.

Iron deficiency anemia is not the only type of anemia. However, this type accounts for more than 90% of all cases of anemia.

Daily dose of iron for anemia

The human body contains from 2.5 to 4.5 g of iron. This amount is not constant and must be replenished regularly.

Women especially suffer from iron deficiency. This is due to the systematic loss of the microelement with menstrual bleeding, as well as a special structure of hormonal processes. The average amount of the element that a woman needs per day is 15 mg, and during pregnancy and breastfeeding - no less than 20 mg.

For normal processes to occur in a man's body, it is necessary to replenish the supply of 10 mg of iron per day.

Children up to 18 years of age should receive 5 to 15 mg of the micronutrient daily (the older the age, the greater the need).

The same statistics claim that in the modern diet of most people the iron level does not "reach" the required norm. On average, a person replenishes his daily "iron" reserve by only 10-20%. Therefore, for many people, iron for anemia must be taken additionally, in the form of complex preparations.

To find out if your body has enough microelements, you need to take a standard biochemical blood test. Normal values are:

• for men – 11.64-30.43 μmol per liter;
• for women – 8.95-30.43 μmol per liter;
• for a newborn baby – 17.9-44.8 μmol per liter;
• for a one-year-old child – 7.16-17.9 µmol per liter.

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Indications iron for anemia

Iron deficiency conditions are diagnosed very often. In the vast majority of cases, they are provoked by unbalanced nutrition or strict monotonous diets.

Among other causes of iron deficiency, it is worth noting conditions in which the microelement is actively consumed. For example, this occurs during puberty, during pregnancy and breastfeeding, as well as after injuries, surgeries, menstrual irregularities, gastrointestinal diseases, parasitic infestations, thyroid disorders, vitamin deficiency of ascorbic acid and B vitamins.

A sharp weakening of the immune system, caused by anemia, gradually becomes the cause of chronic inflammatory processes, the development of cardiac failure, and liver disease.

Iron deficiency in expectant mothers poses a great danger: in such situations, children may be born with existing anemic conditions.

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Release form

The main iron preparations are divided according to the possibility of administration into the body:

• oral (for internal use);
• parenteral (for injection).

In addition, iron-containing medications are divided into different forms, depending on the absorption mechanism. Thus, there are two types of drugs:

• divalent, which are absorbed quickly and completely (administered orally);
• trivalent, which are not fully absorbed (administered by injection).

Iron-containing preparation is absorbed in the digestive system, but for this process to proceed normally, an adequate acidic environment in the stomach is necessary. Therefore, under certain circumstances - for example, with reduced acidity, iron may be absorbed somewhat worse, as well as with the simultaneous use of certain drugs that neutralize acid.

All this must be taken into account when choosing the form of medication.

Iron supplements for anemia

Iron in the form of medical preparations is the basic means with which the treatment of persistent iron deficiency anemia begins. Such preparations consist of salts or complexes of divalent and trivalent iron.

This category includes medications that contain thirty or more mg of the active ingredient in the form of elemental iron.

If the microelement is contained in an amount less than 30 mg, then it is permitted to be used only for preventive purposes.

By the way, eliminating anemia is not the only use of such medications. They are prescribed during the recovery period after prolonged infectious diseases, with lactose deficiency, with enterocolitis, after extensive injuries and burns, with parasitic pathologies, etc.

Iron for anemia is prescribed only by a doctor, after studying the results of a blood test.

Medicines with salts of divalent iron are produced in different medicinal forms. All of them have excellent digestibility, but even a slight excess of dosage can lead to the development of side effects.

The indicated drugs are taken on an empty stomach, since there are some products that can impair the absorption of the necessary microelement.

Preparations of divalent iron differ from each other in the content of the latter, as well as in the completeness of absorption. For example:

• iron sulfate is the most easily absorbed (microelement content from 12 to 16%);
• second on the list is iron chloride (content – up to 6%);
• third on the list is iron furamate (microelement content – up to 16%);
• Iron gluconate (contains up to 22% iron) and iron lactate (up to 9% iron) are absorbed slightly worse.

To avoid irritating effects on the intestinal mucosa, divalent preparations contain mucoproteose.

Trivalent iron preparations for anemia are less bioavailable and are almost not absorbed in the intestine, so they are not widely used. They are used in combination with amino acid-maltose complexes to reduce toxicity.

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Iron tablets for anemia

To correct iron levels in anemia, tablet forms of drugs are most often prescribed:

• Actiferrin is an iron-containing medication that is produced in capsules, oral solution or syrup. The drug is designed to replenish iron deficiency, and its effect is potentiated by the α-amino acid serine present in the composition. Such iron is well absorbed in case of anemia and quickly enters the systemic circulation, which contributes to the rapid regression of the signs of the disease. Adult patients take the encapsulated form of Actiferrin - one piece up to three times a day. If the patient has poor tolerance to the drug, the dosage is reduced to 1-2 capsules per day. In this case, the duration of therapy increases accordingly. Actiferrin is allowed for use by pregnant and lactating patients.
• Ferrogradumet is a prolonged-release medication based on the action of divalent iron sulfate. Each tablet corresponds to 105 mg of elemental iron. The drug is characterized by increased activity and helps to compensate for the lack of a microelement in a short period of time. Ferrogradumet is appropriate for the treatment and prevention of anemic conditions. People prone to anemia are recommended to take one tablet daily for 2-3 months. In case of diagnosed iron deficiency, take 1-2 tablets daily for several months (according to individual indications, it is permissible to take the drug for up to six months). Pregnancy is not a contraindication to therapy with the drug.
• Fenuls is a combination product, in which iron is successfully supplemented with multivitamins. The presence of ascorbic acid and B-group vitamins accelerates and facilitates the absorption of the microelement, and also minimizes its prooxidant effect. Fenuls is taken according to the following scheme:
  • to support the body during heavy menstrual bleeding - one capsule the day before the onset of menstruation and daily until the second day after the end of menstruation;
  • for latent anemia – one capsule for 4 weeks;
  • for severe anemia with iron deficiency - one capsule in the morning and evening for twelve weeks.

Pregnant patients can take the medication as early as week 14. The course lasts two weeks, then there is a one-week break, and so on until the baby is born (unless the doctor prescribes a different regimen).

• Sorbifer is an anti-anemic drug that is a combination of iron and ascorbic acid. The drug is manufactured using a unique technology that provides for the gradual absorption of iron. This allows avoiding many side effects, including a sharp increase in the content of the microelement in the digestive system. Sorbifer is taken one tablet in the morning and evening, shortly before meals. Pregnant patients can also take the drug:
  • I and II trimester – one tablet daily;
  • III trimester and lactation – two tablets daily.

The total period of admission is from two to six months.

• Maltofer is available in the form of tablets for internal use and in the form of chewable tablets, as well as in the form of syrup and solution. The composition of the drug is represented by iron (III) hydroxide polymaltose complex. Chewing tablets can be swallowed whole or chewed with water. The dosage for adults can be from 100 to 300 mg daily, for 1-2 months. The question of the use of this medication during pregnancy has not yet been finally resolved, since studies for this period have not been conducted. Maltofer can be taken in the II and III trimesters.
• Heferol is represented by iron fumarate - in the amount of 350 mg, which corresponds to 115 mg of elemental iron. Heferol has an enteric coating, due to which, when using the drug, contact of iron with tooth enamel and mucous tissues of the stomach is excluded. The drug is taken half an hour before meals, one capsule per day (rarely - 2 capsules, in case of severe anemia). The course of treatment usually lasts 1.5-3 months.
• Gino-Tardiferon is a combination medication based on divalent iron, folic acid and vitamin C. The drug restores iron levels, stimulates hematopoiesis, and is especially recommended for women during pregnancy. The medication is not suitable for treating anemia in children under seven years of age. Gino-Tardiferon is taken before meals, with water (at least 200 ml), in the amount of 1-2 tablets per day. Approximately equal intervals (12 or 24 hours) should be maintained between doses of the medication.

Chelated iron for anemia

When speaking about chelated iron, we mean complex compounds of iron ions with amino acids. In a simpler and more accessible presentation, a chelated form is a drug that is absorbed by the body more easily than others. That is, its biological availability is significantly higher, which means that the body will receive the required amount of iron in full.

What is the essence of the effectiveness of such medications?

Iron ions, being inside the amino acid shell, are ready for absorption without additional transformations in the body. They are immediately used for their intended purpose and are quickly absorbed.

The absorption mechanism is carried out in the small intestine in the following way: a free iron ion combines with a transport protein, which transfers it into the bloodstream. Such a process is called "organic chelation". Without such a process, the body is unable to recognize the microelement as a vital substance and does not accept it for use.

Most often, this happens with inorganic mineral salts, which, for normal absorption, need to go through several successive stages: this is the stage of splitting, dissolution, absorption.

Inorganic mineral salts after their intake become biologically available by no more than 10-20%. This means that the rest of the salts will not be absorbed and may even cause some harm to the body (with prolonged intake).

Chelates have an adequate level of acidity and do not react with the acidic environment of the stomach. This cannot be said about inorganic mineral salts that alkalize the acidic contents of the stomach after oral administration: this can lead to unpleasant sensations such as increased gas formation, deterioration in the absorption of nutrients.

Treatment of anemia with chelated forms of iron is guaranteed to satisfy the body's need for the microelement.

A strong connection with amino acids potentiates the transport of iron ions and provides protection from aggressive gastric acid.

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Iron injections for anemia

Injections of iron medications are not prescribed to everyone, as oral administration is initially more preferable. Injections are used only in the following cases:

• in chronic diseases of the digestive tract, which can negatively affect the absorption of iron (this happens with pancreatitis, enteritis, celiac disease, malabsorption syndrome, etc.);
• for nonspecific ulcerative colitis;
• in case of hypersensitivity to iron salts, allergies;
• in the acute stage of gastric ulcer and duodenal ulcer;
• after surgery involving gastric resection or partial intestinal resection.

Injections are also prescribed in situations where it is necessary to deliver the necessary microelement to the patient’s body in the shortest possible time – for example, this may be relevant before operations.

The most well-known injectable drugs are:

• Ferrum Lek - the active components of the drug are dextran and iron hydroxide. Injections are made intramuscularly, the dosage is calculated individually, depending on the overall deficiency of the microelement. The maximum daily dosage for adults is 200 mg or two ampoules of the drug (4 ml).
• Zhektofer is a combined iron-containing agent that restores iron reserves without affecting hematopoietic mechanisms. The medication is administered intramuscularly, at a rate of 1.5 mg of iron per 1 kg of the patient's weight. Injections are repeated daily or once every two days. The concentration of iron in the blood plasma should be monitored throughout the treatment period.
• Venofer - the drug contains iron hydroxide of sucrose complexes. The solution is administered only intravenously - in the form of injections or droppers. Other methods of administration are prohibited.
• Ferrlecit is a medicine based on the action of active sodium-iron gluconate complex. The drug is administered intravenously, slowly. The average single dose is one ampoule, the frequency of administration is up to 2 times a day. During the infusion, the patient should be in a lying position.
• Ferkoven - consists of iron saccharate, cobalt gluconate, etc., is a hematopoiesis stimulant. The drug is administered intravenously daily for two weeks. The first and second injections are 2 ml, then 5 ml. The infusions should be slow, over ten minutes, so the procedure is only performed in hospital settings.
• Ferbitol is an iron-sorbitol complex drug. It is prescribed for the treatment of hypochromic iron deficiency anemia, in which a drop in hemoglobin levels is associated with impaired intake, absorption or excretion of iron. Ferbitol is administered as intramuscular injections of 2 ml every day. A course of treatment consists of 15-30 injections. Among the main contraindications is hemochromatosis.

Liquid iron for anemia

Liquid preparations containing iron are used primarily to treat anemia in children. Of course, it is easier to give a child a liquid medicine or syrup than a tablet or capsule. However, there is a warning: after taking a dose of such a solution or syrup, the child should drink some water or rinse his mouth so as not to cause darkening of the tooth enamel.

Among the most common liquid iron-containing products are the following:

• Aktiferrin - contains iron sulfate and α-amino acid serine, which accelerates the absorption of iron in anemia. For infants, you can use a medicinal solution, and for children from 2 years of age - Aktiferrin syrup.
• Ferlatum is an anti-anemic agent in liquid form. The solution contains protein succinate, which creates protection for the mucous tissues of the digestive system from the irritating effects of iron. Ferlatum is approved for use in the treatment of anemia even in newborn babies.
• Maltofer is a medication with trivalent iron (hydroxide polymaltosate). The product is used in the form of a syrup or a solution (can be given to infants and premature babies).
• Ferrum Lek is a trivalent iron preparation used from birth. It is produced in the form of a solution and syrup.

Pharmacodynamics

Iron is an important component of hemoglobin, myoglobin and other enzyme substances. The functional focus of iron is the transfer of electrons and oxygen molecules, ensuring oxidative metabolic processes during the development of tissue structures. As part of enzymes, the microelement acts as a catalyst for oxidation, hydroxylation and other important metabolic reactions.

The state of iron deficiency increases with low iron intake from food, with impaired absorption in the gastrointestinal tract, or with hyper-need for iron (for example, after heavy blood loss, during pregnancy, during puberty).

In plasma fluid, iron is transported by the β-globulin transferrin, produced in the liver. One molecule of β-globulin binds to a pair of iron atoms. In combination with transferrin, iron is transported to cellular structures: there it undergoes feedback with ferritin and is used to produce, in particular, hemoglobin.

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Pharmacokinetics

After the injection of iron-containing drugs, the microelement is absorbed mainly through the lymphatic system and is mixed with the blood within approximately three days.

There is no information on the bioavailability of the drugs, but it can be said that quite a lot of the active components of iron-containing drugs remain in muscle tissue for a long time.

Iron binds to ferritin or hemosiderin, and partially to transferrin, after which it is included in the processes of hemoglobin synthesis. Dextran undergoes metabolic reactions or is excreted. The volume of iron excreted from the body is insignificant.

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Dosing and administration

In the vast majority of situations, if a patient needs to take additional iron for anemia, the doctor will prescribe one of the oral medications. Injections are used only in isolated cases.

The amount of a particular drug, the frequency and regimen of administration are determined during an individual consultation. Among the general recommendations, the following can be indicated:

• for adults, the basic dose is calculated using the formula 2 mg/kg of body weight;
• Most often, the daily dose is determined as 100-200 mg of medication, less often – more, for example – up to 300 mg.

With a properly selected daily dose of iron preparation, the signs of anemia recede within a few days. Patients note an improvement in mood, a surge of strength, etc. If you monitor the dynamics using laboratory tests, you can note positive changes in the number of reticulocytes already in the first week from the beginning of treatment for anemia. Persistent stabilization of hemoglobin levels is noted over 2-3 months of treatment.

Experts explain: iron replenishment in anemia occurs quite slowly, so the intake of appropriate drugs should be long-term. If the hemoglobin level has risen to the required level, then there is no need to stop treatment abruptly: usually the drugs are taken for some time to ensure a supply of the microelement. However, the dosage in this case is reduced by about half.

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Use iron for anemia during pregnancy

Women expecting a child often suffer from anemia, because their body must be provided with vitamins and minerals twice as much. But if it is necessary to take additional medications with iron for anemia, they are prescribed only by a doctor, and the dosage is selected as minimally permissible.

It happens that pregnant women are advised to take iron-containing drugs for preventive purposes - this issue is also decided by the doctor.

Among the general tips regarding taking such medications during pregnancy, the following can be noted:

• in the case of a normal pregnancy, a woman may be recommended to take medications containing iron during the third trimester (dosage – approximately 30 mg/day);
• in case of normal pregnancy, for a woman with a tendency to anemia, it is recommended to take iron-containing drugs from the 21st to the 25th week of gestation (dosage - 30 mg once every three days);
• in case of diagnosed iron deficiency during pregnancy, it is recommended to take 100 to 200 mg of iron in the form of various preparations (the dosage varies depending on body weight);
• If anemia is diagnosed even before pregnancy, it is recommended to take the appropriate medications throughout the entire period of gestation and breastfeeding (dosage - 200 mg/day).

All questions regarding the use of iron-containing medications or other medications by pregnant women should be discussed with a doctor to avoid negative results.

Contraindications

Before you start taking a medication containing iron, you need to familiarize yourself with a number of warnings, which are categorical and conditional contraindications.

The following are considered categorical contraindications:

• malignant blood diseases;
• hemolytic anemia, aplastic anemia;
• chronic inflammatory processes in the kidneys or liver.

Conditional contraindications include:

• treatment with antacids and tetracycline antibiotics;
• a diet with increased consumption of foods containing calcium and fiber;
• frequent consumption of large amounts of caffeinated beverages;
• ulcerative processes in the digestive tract, enterocolitis.

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Side effects iron for anemia

Oral use of iron supplements for anemia is sometimes accompanied by undesirable side effects:

• unpleasant sensations in the abdomen - from slight nausea to bouts of vomiting, which are in no way related to food intake;
• loss of appetite, up to and including complete aversion to food;
• the appearance of a metallic taste in the mouth;
• problems with bowel function (for example, difficulties with defecation may alternate with diarrhea).

There are cases when during the period of taking iron medications, the formation of a grayish plaque was observed. To avoid this, doctors advise rinsing the mouth well after taking a tablet or solution.

When iron is injected for anemia, seals may form at the injection site, inflammatory processes, abscesses, allergies, and DIC syndrome may develop.

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Overdose

If an overdose of iron-containing drugs occurs, the symptoms indicated in the list of side effects occur. In addition, symptoms may include nausea, dizziness, confusion, changes in blood pressure, weakness, and hyperventilation.

If you suspect that you have taken an excessive dose of iron, you should immediately wash out the victim's stomach by inducing vomiting. Then the patient should eat several raw eggs and/or drink milk.

Further treatment depends on the symptoms detected.

If an excessive amount of iron-containing agent was injected, acute poisoning occurs, accompanied by overload of the body. Such patients are treated only in a hospital under the supervision of medical personnel.

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Interactions with other drugs

As a rule, iron medications for anemia cannot be combined with substances that can slow down the absorption of the microelement. Such substances include calcium-based drugs, antacids, Levomycetin, tetracycline antibiotics.

You should not take iron supplements with milk, alkaline mineral water, coffee or strong tea. The optimal liquid for this is considered to be plain clean water.

On the contrary, such preparations as vitamin C, citric or succinic acid, sorbitol promote normal absorption of the microelement. The hemoglobin level will be restored faster if, along with iron, the patient takes preparations with copper, cobalt, and B vitamins.

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Storage conditions

Iron-based medications used to treat anemia are usually stored at room temperature, not exceeding +25°C.

Do not freeze medications or expose them to high temperatures, such as leaving them near heating devices or in direct sunlight.

Children should not have access to places where medicines, including iron-containing medicines, are stored.

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Shelf life

Each individual medication has its own shelf life, the duration of which must be clarified by carefully studying the instructions for the drug. On average, iron-containing drugs are stored for three or five years - if the basic principles for storing a particular drug are observed.

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Reviews

Before taking iron-containing medications, you need to assess the degree of anemia by taking laboratory tests. Only then can you begin treatment. According to reviews received from doctors, iron-containing drugs are relevant only in the following situations:

• if dietary correction did not lead to a persistent increase in hemoglobin levels;
• if a patient with anemia is about to undergo surgery during which blood loss is possible;
• pregnant women with a tendency to anemia;
• in case of heavy monthly bleeding in women;
• if the patient's hemoglobin level drops rapidly (the indicators worsen with each week);
• if there is no possibility of correcting the diet (for example, there are contraindications to the consumption of most products).

Every person should know the basic signs of iron deficiency in order to recognize anemia in a timely manner and consult a doctor. Such signs are:

• constant feeling of weakness, headache;
• severe fatigue, irritability, tendency to depression;
• tachycardia, discomfort in the area of the heart projection;
• weak immunity, frequent inflammatory processes.

According to reviews, in order to avoid the development of an anemic condition, people with a tendency to anemia can take 1-2 courses of iron-containing medications annually. Such preventive treatment must be carried out under the control of the hemoglobin level in the blood in order to prevent an overdose.

Treatment with iron-containing medications will be correct and effective if you follow these medical recommendations:

• it is not possible to carry out treatment with more than one iron-containing drug at the same time, regardless of its dosage form;
• It is better if the medication contains additional substances that improve the absorption of iron;
• You cannot take iron-containing medications without first undergoing tests, or prescribe them to yourself;
• During the entire treatment period, you should adhere to the healthiest possible diet and lifestyle.

Smoking, drinking alcohol and caffeinated beverages negatively affect the absorption of iron: this must be taken into account when taking appropriate medications.

Iron Rich Foods for Anemia

If a laboratory analysis indicates a lack of iron in the body, you should not always immediately go to the pharmacist and buy an iron-containing drug. First, you need to consult a doctor: it is possible that there are problems in the body that prevent the normal absorption of the microelement. In such a situation, even complex drugs will not demonstrate the expected effect.

If iron deficiency is caused by an imbalance in the diet, then this situation can be corrected by simply adjusting the daily menu.

It is necessary to include in the list of daily consumed products those that contain a sufficient amount of iron. For example, the most common and accessible sources are considered to be:

• beef, pork;
• liver;
• mussels, oysters;
• various nuts;
• eggs;
• beans;
• grenades;
• apples;
• dried fruits (for example, raisins and figs contain enough iron).

In order for the microelement to be absorbed to the maximum, the food must contain vitamins C and B ₁₂, which are found in the following products:

• berries;
• rose hips;
• cabbage;
• citrus fruits;
• seafood.

In many cases, it is possible to correct the situation with anemia only by adjusting the diet. Most often, the hemoglobin level stabilizes within the first month after making changes to the diet.

The most effective iron supplements for anemia

Almost all combination drugs containing iron are effective against anemia. It is good if such drugs contain components that improve their absorption - for example, vitamin C and amino acids.

It is worth paying attention: many iron-containing medications have a prolonged effect. That is, the release of the microelement in them occurs slowly, which reduces the risk of developing side effects.

To ensure that the drug you choose from the pharmacy is as effective as possible, you need to follow certain rules for taking it:

• iron-containing products should not be washed down with tea, coffee, milk, jelly, alkaline mineral water (it is better to take regular water or juice);
• the effect of the medication is impaired by the simultaneous or sequential intake of substances containing calcium, antacids, antibiotics;
• if it is necessary to give an iron-containing complex to a baby, then it is worth choosing a remedy in the form of a solution or syrup (you should not grind the tablet or pour the contents of the capsule into food or drinks);
• Do not take a double dose of the medication if one dose is missed;
• During treatment with iron-containing drugs, stool may become dark in color: this is normal, there is no need to stop treatment.

And remember: iron for anemia is not just a harmless vitamin preparation, it should be prescribed by a doctor. And treatment should be carried out against the background of periodic laboratory monitoring.