Compositions are provided, which comprise at least one nucleoside analogue inhibitor, pharmaceutically acceptable salts, solvates, or prodrugs thereof and fusaric acid, derivatives, or pharmaceutically acceptable salts thereof. Pharmaceutical compositions comprising the above compositions are also provided that optionally further include another therapeutically effective compound, such as a carrier. Systemic and topical preparations comprising the above compositions are also provided as well as methods of treating viral diseases by the administration of the above antiviral agents to a patient.