The precise definition of 'lifestyle' drugs is a subject of debate. However, they are generally defined as drugs taken to satisfy a non-medical or non-health-related goal. Although the term has been used only recently, the media debate that surrounds these agents, fuelled by the release of medicines such as Viagra (sildenafil), is intense. The increasing availability of drugs that can be used to alter our appearance, our physical and mental capabilities or even our characters is changing the social fabric of our culture and poses a difficult challenge to our healthcare systems. It is also revolutionizing the traditional doctor-patient relationship and raises important issues about the rights to, and limits of, self-diagnosis and self-medication.