Stigma has a significant impact on the diagnosis of a variety of illnesses, patients' compliance with treatment and their recovery from these diseases. However, the Indian medical and nursing curriculum has given relatively little attention to recognising and addressing the issue of stigma. This study compared the perception of stigma with respect to tuberculosis (TB) and diabetes mellitus (DM) among medical and nursing students to that among patients with these diseases. The Explanatory Model Interview Catalogue (EMIC) questionnaire was used for all patients and student groups. Focus group discussions were held with only the students to understand their concept of stigma and the challenges they face while addressing stigma, and to explore their role in addressing stigma. The data showed that patients with TB prefer not to disclose their illness, while DM is not perceived of as stigmatising by patients. As a group, medical and nursing students attached excessive stigma to patients with both DM and TB, and this may mean that medical professionals subconsciously do harm through their interactions with patients and the attitudes they project to society. The perceptions of stigma were linked to the patient's socioeconomic background, apart from the medical condition itself. The students recognised that they lacked the skills to understand and address stigma. We recommend that the subject of stigma be integrated into the curriculum of medical and nursing students.