antibioticsbooks

52 PART 2 Antibacterial Drugs
is needed. Pay attention to the dosing of oral
versus intravenous (IV) penicillins—often, a
conversion from IV to oral therapy means there
will be a substantial decrease in the amount of
active drug in the body.
Many penicillins were developed after the natural
penicillins became available. Until researchers
developed beta-lactamase inhibitors, development
primarily focused on either improved activity
against staphylococci (MSSA) or GNRs ( Figure 6–1 ).
Natural
penicillins
Antistaphylococcal
penicillins
Aminopenicillins
Antipseudomonal
penicillins
Beta-Iactam/beta-lactamase inhibitor combinations
Better against
staphylococci
Better against
GNRs
Figure 6–1
Penicillin Drug Development