Description of the medicine: Benzylpenicillin sodium salt (Benzylpenicillinum-natrium)

BENZYLPENICILLINA SODIUM SALT (Benzylpenicillinum-natrium).

Synonym: Benzylpenicillinum Natricum.

White melkokristallichesky powder bitter taste, slightly hygroscopic. Easily destroyed by the action of acids, alkalis and oxidants, when heated in aqueous solutions, as well as with the action of penicillinase. Slowly destroyed when stored in solutions at room temperature.

Very easily soluble in water, soluble in alcohol.

Theoretically, the activity of the sodium salt of benzylpenicillin is 1670 units per 1 mg, practically the preparation is released with activity of not less than 1600 units per 1 mg.

Benzylpenicillin is active against gram-positive microorganisms (staphylococcus, streptococcus, pneumococcus, diphtheria causative agent, anaerobic spore-forming rods, anthrax rods), Gram-negative cocci (gonococci, meningococci), as well as spirochaetes, certain actinomycetes and other microorganisms. The drug is ineffective against most gram-negative bacteria, rickettsia, viruses, protozoa, fungi.

The action of benzylpenicillin is resistant to strains of staphylococci, which form an enzyme penicillinase, which destroys benzylpenicillin. Low activity of benzylpenicillin against bacteria of the intestinal group, Pseudomonas aeruginosa and other microorganisms is also associated in a certain mantle with the production of penicillinase.

Benzylpenicillin, when administered intramuscularly, is rapidly absorbed into the bloodstream and is found in body fluids and tissues; In the cerebrospinal fluid penetrates in small amounts. The maximum concentration in the blood is observed after intramuscular injection after 30 - 60 minutes. With subcutaneous injection, the rate of absorption is less constant, usually the maximum concentration in the blood is noted after 60 minutes. After 3 to 4 hours after a single intramuscular or subcutaneous injection, only traces of the antibiotic are found in the blood. To maintain the concentration at a sufficiently high level for the required therapeutic effect, it is necessary to inject every 3 to 4 hours. With intravenous administration, the concentration of penicillin in the blood rapidly decreases. When ingested, the drug is poorly absorbed and destroyed by gastric juice and penicillinase, produced by the intestinal microflora. It is allocated mainly by the kidneys.

The concentration and duration of circulation of benzylpenicillin in the blood depend on the amount of the administered dose. The antibiotic penetrates well into the tissues and body fluids. In cerebrospinal fluid it is found to be normal in a small amount, but with inflammation of the meninges its concentration rises.