Body packing by drug smugglers--the transport of illicit drugs in packets swallowed or inserted into body cavities--is a global phenomenon and is becoming more prevalent. The medical care of these patients raises difficult medical and ethical problems. While the medical aspects of treating body packers have been systematically analysed, the ethical issues have received little attention in the literature. The patient may be under police custody or being sought by their criminal patron which may result in imposed interrogations and risky medical procedures. Obtaining informed valid consent for procedures from the patient-detainee may thus be compromised. In addition, physicians may be intimidated by the patient's criminal contacts. This article analyses the conflicts of interest that doctors may face when treating body packers, and proposes some principles to promote institutional guidelines for the treatment of these patients.