Benzathine Benzylpenicillin is a sterile powder made of dibenzylethylenediamine salt of penicillin with an appropriate amount of buffer and suspension aid. The excipients were refined lecithin. After intramuscular injection, the antibacterial active ingredient penicillin is slowly released, which can achieve the purpose of long-acting, so it is also a long-acting penicillin. Benzathine penicillin is for intramuscular injection only, and intravenous injection is strictly prohibited. Because of its long-acting characteristics, it is commonly used clinically to prevent streptococcal infections in rheumatism, and can also be used for the treatment of infections requiring long-term continuous use of penicillin, such as rheumatism and syphilis. Benzathine penicillin is the first choice for the treatment of syphilis, because benzathine penicillin has a significant inhibitory effect on treponema pallidum strains, and so far, no benzathine penicillin resistant to treponema pallidum strains have been found. Benzathine Benzylpenicillin has the advantages of quick action, high cure rate, few side effects and convenient use, so it is the first choice for the treatment of syphilis.

Pharmacological action

Benzathine Benzylpenicillin is a long-acting preparation of penicillin G, which acts as a bactericidal agent by inhibiting the synthesis of bacterial cell walls. Benzathine Benzylpenicillin has strong antibacterial activity against gram-positive coccus such as hemolytic streptococcus, Staphylococcus aureus which does not produce penicillinase, Streptococcus pneumoniae and Gram-negative coccus such as Neisseria meningitidis and Neisseria gonorrhoea. Also sensitive to benzathine penicillin are Corynebacterium diphtheriae, Bacillus anthracis, Clostridium anaerobes, Clostridium perfringens, Clostridium botulinum, actinobacteria, Eubacillus, propionibacterium and other gram-positive bacilli, spirochaetes (treponema pallidum, spirochaeta relapsus, leptospira, etc.) and individual negative bacilli (such as Haemophilus).