157ANTIVIRAL PHARMACOLOGY: DRUG CLASSES AND MECHANISMS OF RESISTANCEThis literature review will cover the antiviral pharmacology based on the drug classes, drug mechanism of action and the resistance pathway of the major viral diseases. It also describes fundamental terms of viral replication, selective toxicity, pharmacokinetics and pharmacodynamics and discusses the significant categories of anti-viral drugs including entry and fusion, nucleoside and non-nucleoside polymerase protease, protease, and integrase, neuraminidase, immune-modulating, monoclonal antibodies and host-directed therapies. Its clinical application in HIV, hepatitis B, C, influenza, herpesviruses, and in new infections as SARS-CoV-2, Ebola, Nipah and Zika is listed. The mechanisms of antiviral resistance, the viral reservoir, cross and multidrug resistance are addressed with their impact on failure to treat, morbidity and the health of the population. Finally, prevention and management of resistance and directions are covered in the review, including broad-spectrum and nanotechnology-enabled antivirals, CRISPR, RNA-based treatments, AI-driven design, precision virology, and surveillance of resistance globally. This common opinion supports reasonable application of antivirals and technological advances in pandemic preparedness at the international scalebattuharshavardininayak@gmail.comResearch1612026Pharmacology of antivirals; Drug resistance; Viral replication; Direct-acting antivirals; Precision virology.Harsha Vardhini B1* Honey Sriya N1, Navya Sri N1, Anjali A,Dr. Akila C RPharm. D V Year Student, Department of Pharmacy Practice, KLR Pharmacy College, Paloncha, Telangana, India.,2Professor, Department of Pharmacology, KLR Pharmacy College, Paloncha, Telangana, India