While considerable attention has been directed at the important role of intravenous drug use in the spread of human immunodeficiency virus (HIV) and hepatitis B, little research to date has been conducted on the role of medicine injections in disease transmission. This is the case despite the fact that (a) the number of medicine injections is several orders of magnitude greater than injections of illegal drugs and (b) the networks of people potentially affected by contaminated medicine injection paraphernalia is far wider. In this article we examine the medicine injecting practices of a random sample of 40 registered medical practitioners (RMP) who have not had formal training in allopathic medicine (do not have MBBS or MD degrees) in Tamil Nadu, India. Attention is drawn to: (a) the lack of vigilance practitioners exercise in maintaining hygienic needles and syringes, (b) their perceptions of what constitutes acceptable hygienic procedure and (c) how patients respond in contexts where they are able to purchase disposable needles and syringes directly from practitioners or from the open market prior to visiting a practitioner. Study results are a cause for alarm and indicate widespread contamination of injection paraphernalia as well as common reuse of disposable needles. The study was confined to RMPs and the researchers strongly suggest that future studies of MBBS trained doctors practising in the public and private sectors be carried out. A structured observation instrument developed to record needle and syringe contamination during the process of injection administration is provided.