OBJECTIVES:  This study analyzes the influence of intellectual property rights protection on the profile of drug request by litigation in the Health Department of Minas Gerais state (SES-MG), Brasil, the public spending and its interfaces with the rational use of drugs and the incorporation of new technologies in the Unified Health System (SUS).  METHODS: This is a descriptive observational study of litigation by drugs attended by SES-MG. There were analyzed 4,140 records of lawsuits in 2010 attended by SES-MG and 1,065 rulings published in the website of the Court of Minas Gerais State, in the period from 2007 to 2009.  RESULTS: In 2010, SES-MG attended 28,104 prescriptions requirement of legalization, the average being 2.2 medications per patient. The prevalence of polypharmacy was 10.6%. In addition to individual lawsuits, the SES-MG attended 19 civil suits which included 135 medicines. The ten most demanded drugs were protected by patents. Of these, only three were included on the list of essential medicines. For all products there were prescriptions by brand name, an average of 50% of the requests had required supply trademark. The survey indicated a prevalence of jurisprudential injunction and the use of prescription drugs cited as evidence, without medical expertise. Ensuring the constitutional right to health was the speech used in more shares. It was observed that the lawsuits are at odds with the rational use of medicines recommended by World Health Organization (WHO). CONCLUSIONS: The annual expense to ensure access to medicines for litigation is growing and represents a major challenge for the public manager. The high prevalence of new medicines prescribed by trademark and growth of biological drug prescriptions show the need to review and strengthen the policy of generic drugs in Brazil.