Theextended-spectrum penicillins are a group ofantibiotics that have the widest antibacterial spectrum of allpenicillins.[1] Some sources identify them withantipseudomonal penicillins,[2] others consider these types to be distinct.[3] This group includes thecarboxypenicillins and theureidopenicillins.Aminopenicillins, in contrast, do not have activity againstPseudomonas species, as their positively charged amino group does not hinder degradation by bacterially producedbeta-lactamases.[4]