Beta-lactam/aminoglycoside combinations: interactions and their mechanisms.

Combinations of beta-lactams with aminoglycosides are widely used in the therapy of infections. There are a number of theoretic advantages to using such combinations. Indeed, combinations of beta-lactams and aminoglycosides usually result in synergism or indifference and very rarely in antagonism. The mechanisms of synergism, resistance to synergism, and antagonism have been studied extensively in enterococci; further studies are necessary to define such mechanisms in other organisms.