Corticosteroids have been used to treat infectious diseases for more than 50 years but, although it has been shown that they are highly effective in improving the clinical course of some diseases, their effects have not been clearly defined in others. Nevertheless, they are still used by a considerable number of physicians. This review analyses the role of systemic corticosteroids in the treatment of acute pharyngitis (AP), community-acquired pneumonia (CAP) and acute otitis media (AOM). A number of trials involving patients with AP have been carried out, but most are marred by methodological flaws that do not allow any firm conclusions to be drawn. The number of trials involving CAP patients is even higher, and the data suggest that corticosteroids may reduce the risk of death only in patients with severe disease. There are very few data concerning AOM, and there is currently no reason for prescribing corticosteroids to treat it. Overall, the data showed that there is, currently, no indication for the universal use of systemic corticosteroids in any of the reviewed diseases and, further, high-quality studies of all of these respiratory tract infections are needed in order to identify the patients for whom the prescription of corticosteroids is rationally acceptable.