Blood pressure reduction is associated with significant reduction in adverse cardiovascular outcomes. Certain blood pressure-lowering drugs have adverse effects on glucose homeostasis, and have been associated with the development of both prediabetes and diabetes during use. There is controversy over the significance of diabetes that develops during treatment with antihypertensives and whether the benefits of blood pressure reduction offset the hazards of dysglycemia that can lead to diabetes. Many treatment guidelines have recently undergone revisions to include consideration for the metabolic effects of antihypertensive drugs, particularly in high-risk populations. This review summarizes the data related to the benefits of blood pressure reduction as well as the adverse metabolic effects and new-onset diabetes associated with some medications.