BENZYL PENICILLIN (PENICILLIN -G) ; used, Side effects, dose, pharmacodynamic, mechanism of action....

 BENZYL PENICILLIN (PENICILLIN -G) 

BRAND NAME :- BENZYLPENICILLIN 0.5,1 MU inj.

BENZYL PENICILLIN, also known as penicillin G and  is an antibiotic used to treat a number of bacterial infections.

PHARMACODYNAMIC:-

Benzathine penicillin is in a class of beta-lactam antimicrobials. Beta-lactams are bactericidal antimicrobials. This type of antimicrobial inhibits the biosynthesis of the cell wall peptidoglycan during the stage of active multiplication. It inhibits bacterial peptidoglycan transpeptidase .It is part of the penicillin and beta lactam family of antibacterial drugs. 

MECHANISM OF ACTION:-

 PROCAINE benzylpenicillin is hydrolyzed into penicillin G once it is released from the injection site. Penicillin G attaches to the penicillin-binding proteins on bacterial cell wall and inhibit the transpeptidation enzyme that crosslinks the peptide chains attached to the backbone of the peptidoglycan. The final bactericidal event involves the inactivation of an inhibitor of autolytic enzymes in the cell wall, leading to lysis of the bacterium . It not active against the penicillinase - producing bacteria which includes many strains of staphylococci .

USED:-

mainly used for the treatment of infections caused by gram-positive cocci,against gram-positive organisms. Some gram-negative organisms such as Neisseria gonorrhoeae and Leptospira weilii are also reported to be susceptible to benzylpenicillin. 

SIDE EFFECTS:-

Common side effect are 

Rash,Allergic reaction,Injection site reactions (pain, swelling, redness).

DOES:- 

DIRECTION BY the PHYSICIAN .

-----------------------------------------------------------------------------------------------------

REPOSITORY PENICILLIN G INJECTIONS 

These are insoluble salts of PnG which must be given by deep i.m.(never i.v.) Injection. They release PnG slowly at the site of injection, which then meets the same fate as soluble PnG.

1). PROCAINE PENICILLIN G inj. 0.5—1 MU i.m . 12-24 hourly as aqueous suspension. Plasma concentrations attained are lower ,but are sustained for 12-24 hours; 

BRAND NAME:- PROCAINE PENICILLIN -G 0.5 ,1 MU dry powder in vial.

FORTIFIED PROCAINE PENICILLIN -G inj: contain 3 lac U procaine penicillin and 1 lac U sod.penicillin G to provide rapid as well as sustained blood levels. 

BRAND NAME:- FORTIFIED P.P. INJ 3+1 lac U vial ; BISTREPEN 6+4 lac U/vial. 

2). BENZATHINE PENICILLIN G 0.6 -2.4 MU i.m. every 2-4 weeks as aqueous suspension. It realease penicillin extremely  slowly — plasma concentrations are very low but remain effective for prophylactic purpose for up to 4 weeks .

BRAND NAME:- PENIDURA -LA ,LONGACILLIN ,PENCOM,0.6,1,2,3MU as dry powder in vial