"Epoetin alfa": instructions for use, reviews and analogues

Uncharacteristic level of hemoglobin concentration is one of the signs of anemia. In fact, it is not yet a diagnosis, but only a symptom that serves as a visiting card for many diseases. The progress of such a pathology may indicate a primary lesion of the blood system.

The erythropoiesis stimulant, known by the international nonproprietary name as "Epoetin alfa", is used as a highly effective reagent, its pharmacological properties are directed to the treatment and prevention of anemia of various etiologies. Properly selected dosage not only contributes to the stabilization of the component structure of the blood, but also positively affects the work of the heart muscle.

Form release and chemical composition

The drug product is delivered to pharmacies in the form of:

• Sterile disposable syringes with a pre-determined dose (the design provides additional needle protection);
• Solution in vials.

The role of the auxiliary ingredient is given to:

• Injection water;
• Chloride and sodium dihydrate-hydrogenphosphate;
• Polysorbate-80.

The biological activity of the substance in vials can be different. Most often it is one thousand or two thousand international units for every 0.5 ml of liquid. However, other forms of reagent are also on sale, including "Epoetin alfa" 10,000 units / 1 ml.

Mechanism of pharmacological action

The biological and immunological properties of the synthesized preparation are absolutely identical to natural erythropoietin. Therefore, the drug very effectively inhibits the symptoms of anemia and corrects the composition of the blood as a typical glycoprotein. I must say that "Epoetin alfa" is primarily focused on increasing the hematocrit and normalizing the hemoglobin level. Its "cardiac function", as well as the propensity of components to improve blood flow in the tissues, is less pronounced.

Half-life time:

• With intravenous injection - four hours;
• When administered subcutaneously - about a day.

The maximum concentration of the reagent in the plasma should be expected after 12-18 hours.

Pharmacokinetic nuances

During the research it was found that the described drug induces the formation of antibodies in the "latent" mode, and its pharmacological significance in the processes of bone marrow fibrosis is close to zero. The protein fraction of the drug "Epoetin alfa" has about 165 amino acids (58% of the total molecular weight), and this is reflected in the degree and quality of the effect of the components on the division / differentiation of progenitor cells.

Multiple intravenous administration (under condition of absence of renal pathologies) does not lead to accumulation of active substance; Children under the age of 12 are likely to prolong the period T1 / 2 to 6 hours.

Indications for use

"Epoetin alfa" is recommended for use if:

• Anemia is diagnosed as a disorder of the hematopoietic function that accompanies oncological disease (there are nonmyeloid tumors);
• The patient experiences the need for regular hemo- or peritoneal dialysis ;
• There is the question of conducting a comprehensive surgical operation with the use of allogeneic blood transfusions;
• The patient is HIV-infected and is receiving zidovudine-based therapy;
• Effective prevention is required.

Optimal dosing regimen

For the drug "Epoetin alfa" the formula of individual selection of a daily dose is valid. However, the manufacturer's general recommendations are reduced to such provisions and norms:

• At the start of the correction phase: fifty units of action (ED) per kilogram of body weight, but not more than three injections / infusions per week;
• In the absence of visible changes: 75 units / kg at the same interval, but not earlier than a month after the start of treatment;
• In exceptional situations: 100-200 U / kg, strictly adhering to the indicated schedule of injections (step of increase - 25 units / month);
• Maintenance therapy: the dose is prescribed to calculate the hematocrit value within the range of 30-35 vol. %.

As practice shows, for a "standard" the single norm of 30-100 U / kg, which is usually taken at the end of the dialysis procedure, is most often taken. The optimal duration of IV infusion is one to two minutes; With the subcutaneous mechanism for the delivery of the active substance are guided by the same rules.

Classification of probable side effects

On the scenarios of the atypical reaction of the organism to the presence of the components of the drug "Epoetin alfa" the instruction for use informs the following:

• It is possible to visualize the symptoms inherent in influenza viruses - severe dizziness, depression, weakness, fever, acute pain in the joints / muscles;
• Permissible imbalances in the work of the heart and blood lines - a sharp increase in blood pressure, malignant hypertension;
• You can not ignore the risk of thrombocytosis (this disease, although it makes itself felt very rarely, but fraught with serious complications);
• The reagent is able to influence the urinary system by changing the amount of potassium and phosphate in the body (the level of creatinine in the blood plasma is not excluded).

On the skin, irritations caused by the introduction of the drug "Epoetin alfa" are sometimes also noticeable. The instruction, in particular, speaks of rashes, eczema, angioedema. And that is interesting: with subcutaneous injections, the percentage of expression is much higher: for a thousand average cases, about 4 episodes (with IV infusions - only 1.6).

There is no reliable information about the immune changes that would be caused by this substance (only the previously mentioned ability of the drug to induce the formation of antibodies deserves attention).

Contraindications declared by the manufacturer

Judging by the information provided in the official guide, "Epoetin alfa" (analogues such as "Binocritus" and "Eralfon", in this regard are as close as possible to the original) should not be used if:

• Uncontrolled hypertension was diagnosed;
• The patient is hypersensitive to the ingredients;
• Preliminary analysis showed the presence of a critical pathology of the bloodlines;
• The patient suffered a heart attack (this is a foreseeable past);
• There is reason to believe that the normal circulation in the brain has been disrupted.

In other words, the start of therapy should be preceded by a medical examination.

special instructions

"Epoetin alfa" (the trade name of a structurally identical preparation may be different - for example, its analogues may be offered as a substitute: "Aeprin", "Raphoetin-SP", "Epocombe", "Eprex", etc.) Increased caution in relation to people suffering from periodic / chronic disorders of peripheral musculature. This rule is especially important if in an anamnesis episodes of convulsive reactions have already been recorded as a response of the body to the receipt of certain medications.

Will not prevent vigilance and gout. Accents in the first place need to be placed in matters relating to blood pressure and the onset of headache (antihypertensive drugs - one of the options for drug correction course). However, it is equally important to assess the true state of the iron depot (even before regular injections). When the conduct of adequate measures is not reflected in the indicators of blood pressure, the reception of the described pharmacological product is stopped.

It must be remembered that renal failure, oncology and HIV infection are included in the list of diseases, during which, against a background of increasing hematocrit concentration, there is a characteristic decrease in the level of ferritin in the blood plasma. To level disproportions resort to substitution therapy involving Fe-containing reagents.

Samples for hemoglobin should be taken 1 time every 7 days. Also, during the initial two months, regular monitoring of the platelet count is required. And for 5-10 days before the surgical intervention, the medicated card of the patient is injected with substances that have antithrombotic properties.

The manufacturer does not exclude that the components of the drug are capable of affecting certain types of tumors, therefore, monitoring of the patient should not stop even after the active phase of treatment.

What to do in case of an overdose?

"Epoetin alfa" (synonyms-drugs, incidentally, behave in a similar way) when overdose acts according to the algorithms laid down in the chemical formula of recombinant erythropoietin, that is, it provokes polycythemia and fluctuations in the level of hematocrit. Due to the absence of classical antidotes, there are no special measures for deactivating the ingredients - just another medication is simply canceled.

Intentional bloodletting is applicable in emergency cases, when the transcendental hemoglobin indicator signals a real threat to life.

Interaction with medicines

When carrying out multistage complex therapy, it is extremely important to understand the principles of "pharmacological behavior" of the reagent "Epoetin alfa" (the release form, as mentioned above, may be different, but the mechanism of the biochemical reaction does not change from this).

Thus, in particular, parallel administration with blood products positively affects the health dynamics. But we must remember that dilution of one solution by another is unacceptable. Medicinal "union" with cyclosporine is fraught with a decrease in the concentration of the latter (the optimal volume ratio of doses is determined by the experimental method).

Reviews and comments

An analysis of the opinions expressed shows that the greatest number of questions arise when it comes to the available options for solving the same problem. For example, few patients are guided by the differences that exist between such pharmacological products as "Epoetin alfa" and "Epoetin beta".

What's the difference - it's easy to understand if you pay attention to the comments of doctors. The fact is that the structural model of natural erythropoietin is represented by two chains, both of which have the desired effect on the blood system. Producers of the same medicine, because of differences in technology, synthesize either an alpha fragment or a beta.

As for the reviews about the drug itself, many of those who had to test it on themselves, testify that the remedy is quite effective, and in some special cases it is also irreplaceable for certain categories of patients.