Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that may be caused by an adverse drug reaction. We discuss the clinical presentation and outcomes of 52 cases of drug-induced PG reported to date in the literature. We conducted our literature search for case reports of drug-induced PG using keywords on PubMed and Medical Subject Heading (MeSH) terms on MEDLINE and EMBASE. To assess the probability that each case of PG was related to drug therapy, we used the Naranjo criteria. We identified 44 studies in the literature, with a total of 52 cases of drug-induced PG. The mean Naranjo score for cocaine-induced PG (n = 13) was 9.4, indicating a definite adverse drug reaction, while the mean Naranjo scores for isotretinoin (n = 5), propylthiouracil (n = 5), and sunitinib (n = 5) were 6.2, 6.8, and 7.4, respectively, indicating probable adverse drug reactions. Drugs should be considered as a possible triggering event whenever PG is diagnosed, and clinicians should particularly consider this in patients taking isotretinoin, propylthiouracil, or sunitinib, as well as in patients with a history of cocaine use.