The introduction of antipsychotic medications in the clinical practice of psychiatric pharmacotherapy that took place half a century ago was a real revolution. Antipsychotic medications reorientated the organic basis of mental disease and gave a clear therapeutic choice in the treatment of psychotic patients. The gradual application of their use made possible the de-institutionalization of patients as well as the 4th revolution of psychiatry, that is community and social psychiatry. Αntipsychotic medications did not prove to be the solution to every problem that patients faced. This occurred despite the fact that novel drugs were discovered being very effective and deprived of the majority of unwanted side effects of the older drugs. In any case the discovery of antipsychotic medications deserves the title that has been granted to them, and which is that of the second revolution of psychiatry. The knowledge of the basic principles of their pharmacologic actions, their unwanted side-effects and the measures of their prevention and treatment constitute a necessary tool for every nurse; especially when taking into consideration the fact that antipsychotic medications are used in a wide variety of cases even reaching up to the treatment of acute organic brain syndromes, that are highly prevalent in the medical and surgical units of general hospitals. This article deals with the basic principles of nursing process when administering antipsychotic medications. Furthermore, it also deals with the major problem of the compliance of patients to their treatment.