<s>[INST] Hello doctor, I started taking ayurvedic medicines yesterday, and I have noticed that my stool has turned dark or black in color. I am suffering from severe belching and headache. I am taking Somu syrup and Shankh Vati. Last month I had the same problem, for which I took allopathic medicines. [/INST] Hello. The problem of black colored stool is called melena. For further queries consult an ayurveda specialist online --> </s>