At present, drug prescription is a hot topic in terms of professional responsibility. Psychiatric-forensic criteria are provided for appropriate drug prescription, focusing on off-label and generic drug prescription. Off-label prescription should be made in accordance with current regulations, in particular with the regulatory requirements related to patient consent. Generic drug prescription is affected by several critical issues, such as drug excipients, equivalence to original drug, correspondence of therapeutic indications. The different spheres of responsibility of physicians and apothecaries in prescribing and distributing drugs, respectively, are discussed. The knowledge of these issues can be helpful for physicians in their clinical practice, allowing preservation of professional autonomy and compliance with current regulations. The explanation of the most common mistakes about drug prescription that are examined in law courts can be the starting point of an interdisciplinary debate involving all interested parties that are called upon to judge psychiatrist responsibility in drug prescription.