Gandhaga Thailam (Medicated oil) is an unique Siddha medicine having Gandhagam (sulphur) , Vediuppu (potassium nitrate), Manosilai (arsenic disulfide), Navacharam (ammonium chloride), and Veeram (mercuric per chloride)as its ingredients. The special feature about the oil is that it can be used an internal medicine. In siddha system this oil is mainly used to treat many skin diseases. Since Gandhaga thailam is a totally mineral based medicine documenting the safety profile of the drug becomes need of the hour. In this study Acute and Sub acute toxicity studies were done for the Gandhaga thailam in Wistar albino rats of both sexes. In acute toxicity study 2000mg of Gandhaga thailam was administered orally as a single dose and the mortality and behavioral changes were monitored for 14 days. No mortality and behavioral changes were observed. Then a repeated oral toxicity study for 28 days was done with 3 doses namely 100mg, 200mg and 400 mg of Gandhaga thailam. Hematological, Biochemical and Histological parameters were observed after 28 days of treatment. No significant abnormality could be observed in any of the mentioned parameters except SGPT which is slightly increased (p < 0.001) compared with the control group. Since there is no positive correlation with any of the other observed parameters and the histological appearance of the liver appears to be normal, It could be claimed that our drug Gandhaga thailam did not produce any toxicity in acute and subacute toxicity studies and it is safe to use upto 400mg .