Vidarabine (Standard) is the analytical standard of Vidarabine. This product is intended for research and analytical applications. Vidarabine (Ara-A) an antiviral agent which is active against herpes simplex and varicella zoster viruses[1][2]. Vidarabine has IC50s of 9.3 µg/ml for HSV-1 and 11.3 µg/ml for HSV-2[2]. Vidarabine also has anti-orthopoxvirus activity[3].