A painful, painful, tumor-like formation at the edge of the anus that is located below the dentate line.　　If one day there is suddenly a lumpy formation with pain at the edge of the anus, the most likely cause is the formation of thrombosed external hemorrhoids. Not all external hemorrhoids are painful, but only thrombosed external hemorrhoids are particularly painful. Blood blisters on the fingers, which probably anyone has experienced, are similar to blisters in external hemorrhoids. External hemorrhoids usually do not bleed, but there are times when they bleed with the rupture of the nucleus of the hemorrhoid with defecation. Although they are external hemorrhoids, there are cases where they are hidden inside the anus and invisible from the outside. For early detection, you need to touch the anus with your fingers apart, and if you touch a lump-like object that is painful, you can consider it to be an external hemorrhoid. When a swollen lump is touched in an area where nothing has grown before, the patient will mostly think that something has grown in the anus, but the more you push in, the more painful it becomes, which is a characteristic of external hemorrhoids, unlike internal hemorrhoids and prolapse.