A pulmonary drug delivery system is disclosed, including a breath-powered, dry powder inhaler, and a cartridge for delivering a dry powder formulation. The inhaler and cartridge can be provided with a drug delivery formulation comprising, for example, a diketopiperazine and an active ingredient, including, small organic molecules, peptides and proteins, including, insulin and glucagon-like peptide 1 for the treatment of disease and disorders, for example, endocrine disease such as diabetes and/or obesity.