Darkening of the intestines after taking rhubarb usually returns to normal. Intestinal blackening usually refers to intestinal melanosis, which is a benign, reversible non-inflammatory bowel disease due to the phagocytosis of a large number of lipofuscin-containing substances by macrophages in the colonic mucosa, which leads to pigmentation and darkening of the intestinal tract. Colorectal melanosis can be caused by long-term use of anthraquinones such as rhubarb and senna or constipation. Usually, it can be gradually relieved after the symptoms of constipation are relieved and the medication is discontinued, and it can usually return to normal. Patients with colorectal melanosis should pay attention to their diet, eat more fresh fruits and vegetables, avoid eating cold, spicy and other stimulating foods, usually pay attention to rest, avoid staying up late, appropriate exercise, and develop good bowel habits. If necessary, you can take domperidone and other pro-dynamic drugs, bifidobacteria and other intestinal probiotic drugs under the guidance of the doctor for treatment. After taking rhubarb intestinal blackening if a long time can not be relieved, it is recommended to consult a doctor in a timely manner, and actively accept the treatment. Drugs need to be taken in strict accordance with the doctor’s instructions, not self-medication, so as not to delay or even aggravate the condition.