indication

For treatment of infection (Respiratory, GI, UTI and meningitis) due to E. coli, P. mirabilis, enterococci, Shigella, S. typhosa and other Salmonella, nonpenicillinase-producing N. gononhoeae, H. influenzae, staphylococci, streptococci including streptoc

pharmacology

Ampicillin is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name "penicillin" can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Ampicillin has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of Ampicillin results from the inhibition of cell wall synthesis and is mediated through Ampicillin binding to penicillin binding proteins (PBPs). Ampicillin is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases.

mechanism of action

By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, Ampicillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that Ampicillin interferes with an autolysin inhibitor.

route of elimination

Ampicillin is excreted largely unchanged in the urine.

drug interactions

Atenolol: Ampicillin decreases bioavailability of atenolol

Demeclocycline: Possible antagonism of action

Doxycycline: Possible antagonism of action

Ethinyl Estradiol: This anti-infectious agent could decrease the effect of the oral contraceptive

Mestranol: This anti-infectious agent could decrease the effect of the oral contraceptive

Methacycline: Possible antagonism of action

Methotrexate: The penicillin increases the effect and toxicity of methotrexate

Minocycline: Possible antagonism of action

Oxytetracycline: Possible antagonism of action

Rolitetracycline: Possible antagonism of action

Tetracycline: Possible antagonism of action