Leucovorin-LENS - instructions for use, dose, side effects, contraindications

Calcium folinate is a restored form of folic acid and is used as an antidote for medicines that act as antagonists of folic acid. This compound is also known as folinic acid.

Folate antagonists, such as methotrexate, inhibit dihydrofolate reductase and, thereby, prevent the formation of tetrahydrofolate from folic acid, which serves as an important cofactor for the transfer of single-carbon residues in the biosynthesis of nucleic acids. As a result, the synthesis of nucleic acids and cell division is blocked. Calcium folinate in contrast to folic acid does not require the reduction of dihydrofolate reductase for conversion into tetrahydrofolate, which allows its application to restore the broken process of biosynthesis of DNA, RNA and proteins. The protective action of calcium folinata is manifested only in relation to healthy cells. Prevents the toxic effect of methotrexate on the cells of the bone marrow and gastrointestinal tract, but does not significantly affect the already provided nephrotoxic effect of methotrexate.

It helps to fill the deficit in the body of folic acid.

Calcium folinate can also enhance the antitumor effect of fluorouracil. When these two drugs interact, a stable complex containing thymidylate synthetase is formed, which inhibits or suppresses the synthesis of DNA.

The beginning of the drug: with intramuscular injection - after 10-20 minutes, with intravenous administration - less than 5 minutes. The duration of action is about 3-6 hours, regardless of the route of administration.

Pharmacokinetics:

The maximum concentration of reduced folate in the blood serum with intramuscular injection is achieved on average in 40 minutes, with intravenous administration - after 10 minutes. Penetrates through the blood-brain barrier in moderate amounts; more accumulates in the liver. Metabolized in the liver and intestinal mucosa mainly in the active metabolite 5-methyltetrahydrofolate. The elimination half-life is 6.2 hours, regardless of the route of administration.

It is excreted by the kidneys of 80-90%, with caloric masses - 5-8%.

Indications:

- Intoxication with folic acid antagonists (methotrexate, trimethoprim and pyrimethamine)

- Prevention of toxic effects of methotrexate when used in high and high doses.

- Colorectal cancer (as part of combination therapy with fluorouracil).

- Megaloblastic anemia in the background of a deficiency of folic acid (including against the background of malabsorption syndrome, malnutrition, pregnancy, sprue, in early childhood with congenital insufficiency dihydrofolate reductase).

Contraindications:

- Hypersensitivity to calcium folinate or any other substance that is part of the drug

- Megaloblastic anemia, caused by a deficiency of cyanocobalamin (a vitamin B₁₂).

Carefully:Alcoholism, epilepsy, chronic renal failure (CRF), children's age (up to 2 years - safety and efficacy for children not established).

Pregnancy and lactation:

Studies of the effect of calcium folinate on reproductive function in animals and humans have not been conducted. It is not known whether calcium folinate harmful effects on the fetus if it is prescribed to pregnant women, and whether it can affect reproductive function. It is not known whether the calcium folinate in the mother's milk.

The use of the drug during pregnancy and lactation is possible only if the intended benefit to the mother exceeds the potential risk to the fetus.

Dosing and Administration:

The solution is administered intramuscularly or intravenously.

In connection with the fact that different schemes of application of Leucovorin-LENS® are used when choosing a specific dose, the physician should be guided by special medical literature.

All the below listed doses are given in accordance with the conversion to folinic acid.

Usually when the drug is administered in combination with high doses of methotrexate (12-15 g / m²) the administration begins 24 hours after the end of treatment with methotrexate at a dose of 10 mg / m² every 6 hours for 72 hours or until the methotrexate concentration in the blood plasma is less than 5x10 ~⁸ M.

In patients with acidic urine reaction, exudative effusions, impaired renal function, intestinal obstruction, a higher dose of Leucovorin-LENS® and / or longer duration of treatment may be required, since the excretion of methotrexate in this group of patients may be delayed. The use of leucovorin-LENS® in these cases is recommended to be based on the mandatory determination of the concentration of methotrexate in the blood plasma. To prevent the development of chronic renal failure, hydration (3 L / day) is performed and administered sodium hydrogen carbonate to maintain the pH of urine at 7 or higher.

At random overdose of methotrexate Leucovorin-LENS® is administered at a dose equal to or greater than the dose of methotrexate administered no later than 1 hour after injection of methotrexate, then the drug is administered every 3 hours to 10 mg / m² until the disappearance of signs of toxicity.

When combined with fluorouracil Leucovorin-LENS® is administered:

- in a dose of 200 mg / m² intravenously slowly (at least 3 minutes) or intravenously drip followed by intravenous fluorouracil at a dose of 370 mg / m² or

- in a dose of 20 mg / m² intravenously followed by intravenous administration of fluorouracil at a dosage of 425 mg / m²

The drugs are administered daily for 5 days at intervals of 4-5 weeks between repeated courses.

In the treatment megaloblastic anemia caused by a deficiency of folic acid Leucovorin-LENS® is prescribed for 1 mg intramuscularly or intravenously per day.

Side effects:

Allergic reactions: skin rash, hives, itching, anaphylactic shock. When using high doses of calcium folinata, dyspeptic disorders are possible. Rarely is sleep disturbance, agitation.

Overdose:

Calcium folinate is not toxic. Even with very high doses of signs of overdose is not observed.

Interaction:

Calcium folinate with simultaneous application reduces the effectiveness of folic acid antagonists.

Reduces anticonvulsant activity of phenobarbital, phenytoin and primidone.

May lead to an increase in both the therapeutic and toxic effects of fluorouracil, and therefore, when combined, fluorouracil doses should be reduced.

Special instructions:

The use of leucovorin-LENS® in pernicious and other megaloblastic anemias caused by a deficiency of cyanocobalamin (vitamin B12) can lead to hematological remission with a simultaneous progression of neurological disorders.

It can increase the frequency of epileptic seizures in children predisposed to them due to a decrease in the effect of antiepileptic drugs - hydantoin derivatives and primidon (hexamidine).

Form release / dosage:

A solution for intravenous and intramuscular administration of 5 mg / ml (10 mg / 2 ml, 25 mg / 5 ml, 50 mg / 10 ml) or 10 mg / ml (ZOMg / Zml, 50 mg / 5 ml, 100 mg / 10 ml ).

Packaging:

For 2 ml, 5 ml or 10 ml (for a dosage of 5 mg / ml) and 3 ml, 5 ml or 10 ml (for a dosage of 10 mg / ml) into the bottles of colorless neutral glass, sealed with rubber stopcaps,aluminum-plastic.

1 bottle of 5 ml or 10 ml together with instructions for use in a pack of cardboard.

5 or 10 bottles of 2 ml, 3 ml or 5 ml, together with the instruction for use, are placed in a bundle with septums or special cardboard receptacles.

For 30, 50, 60 or 100 bottles with an equal number of instructions for use are placed in a box of cardboard (for hospitals).

Storage conditions:

In the dark place at a temperature of no higher than 8 ° C. Keep out of the reach of children.

Shelf life:

2 years.

Do not use after the expiry date printed on the package.

Terms of leave from pharmacies:On prescription

Registration number:LS-002169

Date of registration:23.01.2012 / 27.07.2016

Expiration Date:Unlimited

The owner of the registration certificate:LENS-PHARM, LLC LENS-PHARM, LLC Russia

Manufacturer: & nbsp

VEROPHARM SA Russia

Information update date: & nbsp06.03.2018

Illustrated instructions

Instructions

Leucovorin-LENS® (Leucovorin-LANS®)