Diabetes mellitus remains an incurable condition that is associated with serious complications such as cardiovascular and renal disease. Most people with diabetes will experience type 2 diabetes, with obesity being a major risk factor for its development. Lifestyle modifications remain central to the management of type 2 diabetes, but because of the challenges in maintaining such changes in the long term and the progressive nature of the condition, most patients also require oral medicines and, eventually, injectable medicines. Nurses have an essential role in the education, empowerment and support of patients with type 2 diabetes, and it is important that they understand the available pharmacological treatment options. This article outlines the main types of oral medicines used in type 2 diabetes, including their modes of action, advantages, cautions and side effects, as well as discussing their selection and use in clinical practice.