The human being all over the world seems to be faced with the increasing of the viral diseases. Even there are anti-viral drugs available, but the attempt to find out other anti-viral agents still advised to do. In so doing, a cultural approach could be applied. Herbal medicines which are already used traditionally from generation to generation, is subjected to screen for the anti-viral purposes. From the available Balinese traditional text of medicine, it is found that there are two viral diseases suspected, namely tilas for herpes zoster and kecacar for smallpox in modern medicine. Therefore, the herbal medicinal plants for these two kinds of disease were invented. There are 29 kind of medicinal plants described for tilas, and more than 70 kinds of plants for kecacar. Due to practical reason, only five plants prescribed for herpes zoster analyzed for this study, namely: 1) Alpinia galanga L., 2) Erythrina lithosperma Miq., 3) Sterculia foetida L., 4) Coriandrum sativa L., and 5) Syzygium cumini L. Study was focused on the isolation and their toxicities in terms of LD-50. The results found are as follows: 1) Volatile oil was isolated from Alpinia galangal L.; 2) alkaloid was isolated from Erythrina lithosperma Miq.; 3) flavanoid was isolated from Sterculia foetida L.; 4) volatile oil was isolated from Coriandrum sativum L.; and 5) tannin was isolated from the Syzygium cumini L. Isolation technique used was GC-MS. The LD-50 of the stated plants found are as follows: 1) Alpinia galangal L. 20.0 g/kg body weight; ranged from 13.41-29.84 g/kg body weight; 2) Erythrina lithosperma Miq. 9.83 g/kg body weight, ranged from 8.21-11.77 g/kg body weight; 3) Sterculia foetida L. 20.1 g/kg body weight, ranged from 13.4-29.8 g/kg body weight; 4) Coriandrum sativum L. 5,062 ml/kg body weight, ranged from 4,005.8-6,397.64 ml/kg body weight; 5) Syzygium cumini L. 16.87 g/kg body weight, ranged from 13.35-21.33 g/kg body weight. From the results found, it is concluded: 1) there are two diseases which are suspected caused by viral infection, namely tilas and kecacar; 2) there are 29 kinds of medicinal plants described for tilas disease; 3) the medicinal plants described for kecacar is not reported here; 4) the active components isolated are volatile oil from the Coriandrum sativa L. and Alpinia galanga L; flavonoid from the Sterculia foetida L.; alkaloid from Erythrina lithosperma Miq. and tannin from Syzygium cumini L.; 5) all the plants stated are safe to be used as herbal medicine. For further study is recommended: 1) the anti-viral activity testing is a must for the stated plants, either in vivo or in vitro; 2) the similar study needs to conduct for another plants described traditionally for the same diseases.