Twentieth century Costitutios popularizated the words rights. Since French Revolution some of them recibe the name of Men and citizens rigbts and are invested with a large moral load by pointing them as preceding the.legislator, who bas to admit their existence as men proper rights. Between those rights are the called Bioethic principies some of which were not expressly consecrated in 1991 Colombian Constitution. In this article Lpropose to analyze the principle of informed consent, the proces corresponding which with this principle can be consider as a fundamental right and how that recognition modifies law theory in Colombia.