inhibit transpeptidase rxn (last step of peptidoglycan synthesis)

BLOCK cell wall synthesis/repair: cell swelling and lysis

SE: hypersensitivity, diarrhea, anaphylactic shock, serum sickness (ADJUST FOR RENAL DZ)

distribute all over body, lower in CSF

PENICILLIN SPECTRUM

MAINLY Gram +

some Gram -

spirochetes

bactericidal

PENICILLIN G (IV)

PENICILLIN V (ORAL)

SPECTRUM

t1/2: 30 minutes

only 1/3 of oral Penicillin G absorbed via GI tract

GRAM + cocci (staph, strep, bacilli)

except penicillinase producing S. aureus

Gram + bacilli

Gram - cocci (neisseria spp)

Spirochetes

oral on empty stomach

Procaine Pen G

 Benzathiine Pen G

indications and kinetics

Chlamydia

Gonorrhea

Pneumococcal pneumonia

Oxacillin

Cloxacillin

Dicloxaciilin

Nafcillin

restrict for penicillinase resistant staph.

Acid stable

LESS POTENT THAN PEN G

not active for enterococcus and Listeria

AMPICILLIN

AMOXICILLIN

Indications and kinetics

good oral absorption for both. amoxicillin better

amoxicillin: DOC for prophylactic Bacterial Endocarditis (BE)

resistant from excessive use

combine with inhibitors to protect effect and cover bugs with B-lactamase: Clavulanic acid and sulbactam

AMPICILLIN and AMOXICILLIN

spectrum

BROADER than normal penicillins

Gram + and Gram - (aerobes and most oral anaerobes)

S. pyogenes, S. pneumonia

H. flu

Enterobacteriaceae

E. coli, L. monocytogenes (meningitis)

LESS POTENT THAN PEN G and V

TICARCILLIN

specific purpose pen (anti-pseudomonas)

pseudomonas

indole+ proteus 

bacetericidal

parenteral--poor ora absorbtion

Penillinase sensitive

add clavulanic acid to increase effect to penicillinase+ staphlococci

specific purpose anti-pseudomonas

better oral absorption

bactericidal

specific purpose anti-pseudomonas penicillin

poor oral absorption--> parenteral

MOST POTENT

specific purpsoe antipseudmonas and proteus

MORE active against klebsiella

structurally and pharmacologically related to penicillin--> inhibit cell wall synthesis

covalently bind transpeptidase enzyme and stop cell wall synthesis

Gram + (except enterococci)

G- (proteus, e. coli, klebsiella)

Not active against some oral anaerobes...

first generation --to 3rd: increasing gram - and anaerobe activity,lower g+ activity