EXTRA-LABEL USE OF HUMAN-MEDICINE ANTIMICROBIALS IN THE TREATMENT OF BACTERIAL PNEUMONIA IN DOGS AND CATS: BRAZILIAN REGULATORY FRAMEWORK AND VETERINARIAN TECHNICAL RESPONSIBILITY

Abstract

This article aimed to analyze, from the perspective of the Brazilian regulatory framework, the technical and legal criteria underlying the extra-label (off-label) use of human-medicine antimicrobials in the treatment of bacterial pneumonia in dogs and cats. This is a narrative literature review based on articles indexed in the SciELO and PubMed databases, with a complementary search in Google Scholar, together with applicable Brazilian health legislation, published mostly between 2011 and 2025. The results indicate that Decree No. 5,053/2004 and Collegiate Board Resolution No. 20/2011 of the Brazilian Health Regulatory Agency authorize extra-label prescribing in the country, but do not establish objective technical parameters for this decision, a gap partially filled by pharmacokinetic/pharmacodynamic (PK/PD) principles and international consensus guidelines. Amoxicillin-clavulanate, doxycycline and ciprofloxacin remain among the most frequently used drugs in this modality, each with a distinct clinical and regulatory risk profile. It is concluded that the responsible practice of extra-label prescribing depends on the articulation between the Brazilian legal framework, the available pharmacological evidence and the veterinarian's documented technical judgment, so as to preserve therapeutic efficacy, protect the professional from an ethical-legal standpoint, and contain bacterial resistance.