Methods of using FGF1 analogs, such as FGF1 mutant proteins having an N-terminal deletion, point mutation(s), or combinations thereof, to reduce blood glucose levels in subjects with steroid-induced diabetes, hypercortisolemia, or diabetes due to treatment with an antipsychotic agent, are provided. Such mutant FGF1 proteins can be part of a chimeric protein that includes a β-Klotho-binding protein, an FGFR1-binding protein, a β-Klotho-binding protein and a FGFR1-binding protein, a C-terminal region from FGF19 or FGF21.