• Pediatricians are made familiar with antiviral drugs and are provided with specific recommendations for treatment of viral diseases. The antiviral drugs in clinical use today are discussed in terms of their doses, routes of administration, mechanisms of action, established and potential efficacies, and toxicities. These drugs include acyclovir, amantadine, trisodium phosphonoformate, ganciclovir, ribavirin, rimantadine, vidarabine, and zidovudine. Biologic response modifiers, such as interferons, are mentioned briefly in their historical context. Future trends in antiviral therapy are anticipated with mention of the most promising candidate compounds currently in preclinical trials.