Ethical issues of human experimentation with special reference to informed consent

Human experimentation in order to develop new medical therapies creates very complex ethical problems: when is it possible to test a new therapy on a human subject? Is it always necessary his/her consent? Which information should be given to the subject before requesting his/her consent? How to behave in the case of minors, psychiatric patients and other subjects not perfectly free or able to understand the information provided? Is it right to subject a person to an experimentation from which he/she will not get any direct advantage? Which results can be published? In other words, which are the ethical limits of human experimentation? These are difficult questions, to which the authors tried to answer referring to some ethically significant human experimentations, such as those performed by Lind and Jenner in the XVIII century, and those carried out by the nazi doctors, from whose trial derived the Nuremberg Code, which introduced for the first time, at an international level, the principle of the informed consent. Some of the limits of this document, including the impossibility of doing research on subjects not able to give their informed consent, such as minors and psychiatric patients, were overcome by the Declaration of Helsinki, whose current version resulted from several subsequent revisions. According to this document, a major role is played by the Institutional Review Boards or Institutional Ethical Committees that have the heavy responsibility of evaluating the ethical connotations of human experimentations.