Evaluation of the safety of macrolides.

The safety of all drugs is established by animal studies, administration to healthy volunteers and the observations during clinical studies to confirm efficacy. During these studies, patients are questioned about side-effects and extensive laboratory testing of blood and urine samples is performed. Despite these extensive studies, new problems may arise during post marketing surveillance which is designed to identify any rare side-effects. Today, all studies suggest that macrolides, and especially the more recently developed agents, are well tolerated. Some variations in tolerability may be due to the size of the macrocyclic ring and the presence of different esters. There are very few instances of irreversible organ damage.