Anal fissure is a common anal disease that can cause a lot of pain to patients. Early anal fissures, if detected in time, can be completely healed by conservative treatment for the most part. If recurrent attacks occur over a long period of time, it is inevitable to suffer from the pain of surgery. So in reality, how can we tell if we have anal fissure? Anal fissures generally have three main symptoms: constipation, pain and bleeding. If you are often constipated, the stool is too thick and too hard, and forceful defecation is bound to cause damage to the anus; when you have a stool, there is a feeling of discomfort when the stool passes through the anal opening, such as a burning sensation, a pain like a knife cut, etc. This pain, which is relieved for a short time after defecation, may soon continue to feel unbearable and severe pain, a process that lasts for hours or even a whole day As for blood in the stool, anal fissures can cause blood in the stool, which is bright red, but not too much. This blood in the stool is accompanied by pain, unlike bleeding from internal hemorrhoids, which is not accompanied by pain. In conclusion, it is important to learn about related diseases and take the initiative in your own hands by preventing and treating them early.