The US Food and Drug Administration approved thalidomide and its analogues for 
the treatment of erythema nodosum leprosum, in spite of the notoriety of reports 
of severe birth defects in the middle of the last century. As immunomodulatory 
drugs, thalidomide and its analogues have been used to effectively treat various 
diseases. In the present review, preclinical data about the effects of 
thalidomide and its analogues on the immune system are integrated, including the 
effects of cytokines on transdifferentiation, the anti-inflammatory effect, 
immune cell function regulation and angiogenesis. The present review also 
investigates the latest developments of thalidomide as a therapeutic option for 
the treatment of idiopathic pulmonary fibrosis, skin fibrosis, and 
ophthalmopathies.