A foreign body sensation at the anal opening along with pain may be a sign of hemorrhoids. When the swelling inside the anus is prolapsed and embedded in the anal opening, there will be a foreign body sensation at the anal opening. You can try to incorporate the prolapsed swelling back inside the anus with your hand, and the pain can be relieved to some extent. If it is an inflammatory external hemorrhoid or a thrombosed external hemorrhoid, it is usually difficult to retract, so you can take a sitz bath with warm water or potassium permanganate water to improve the blood circulation around the anus, and the pain can be relieved to some extent, and the swollen swelling can subside. Then apply a hemorrhoid cream at the anal opening, such as anal tide ointment or Ma Yinglong hemorrhoid cream, which can play a role in clearing heat and detoxification, reducing swelling and relieving pain. Eat a light diet and avoid spicy, stimulating and fried foods. Through the above conditioning or treatment, most of the symptoms of anal pain as well as foreign body sensation can be relieved in about 3-5 days.