Medical doctors, surgeons, researchers, and other practitioners in the field are usually bound by the Hippocratic oath and other professional codes to “do no harm” to the patient. Yet they face a growing number of dilemmas that increase the patient’s risk to be harmed, even if that risk is freely and willingly undertaken—specifically when a person requests a procedure or medication with the intention to enhance his or her already-healthy body.

From media headlines, we are already familiar with the dual use of drugs—such as anabolic steroids as both a treatment for sick patients and an enhancement for otherwise-healthy athletes. Patients take psychostimulants such as Ritalin or modafinil to treat attention-deficit hyperactivity disorder, but the same drugs are also illicitly used by students to help focus on their studies. Reconstructive surgery helps to boost the confidence and appearance of patients with damaged or deformed bodies, but in today’s down economy, jobseekers are increasingly turning to cosmetic surgery and Botox injections to improve their appearance and, therefore, their prospects for employment. 

These drugs and procedures are morally questionable, because while they seem to offer some benefits, their unintended effects are not as clear and can be harmful, thus threatening the Hippocratic oath and professional responsibility. Even something as ordinary as drinking alcohol to enhance one’s mood often proves to be a double-edged sword: when a hangover cuts deep into our well-being the morning after, it is difficult to say whether it was worth drinking in the first place.  

Today, human enhancement is primarily driven by pharmacology and other familiar procedures such as cosmetic surgery; but soon it will be inextricably linked to genetic engineering, robotics, nanotechnology, neuroscience, virtual reality, and other emerging areas. Before these ethical dilemmas multiply, let us attend to an unresolved core issue here: If the (alleged) distinction between therapy and enhancement is significant in the moral debate—drawing a line in the sand between what we are permitted to do and what we ought not to do—what exactly is that distinction?