Ch. 41 focuses on antitubercular drugs, which are medications used to treat infections caused by Mycobacterium species, primarily tuberculosis (TB). It outlines the objectives for understanding these drugs, defines key terms related to TB and its treatment, and lists various first-line and second-line antitubercular medications, including drug profiles. The text also discusses the pathophysiology of TB, its transmission, diagnosis, and the factors contributing to the rise of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB). Finally, it covers the mechanisms of action, indications, contraindications, adverse effects, and drug interactions of these medications, providing important information for the nursing process, patient teaching, and safe administration of antitubercular therapy.