What is the best treatment for anal swelling?

See physician: Treatment will always depend upon the diagnosis of the condition. See your physician. If it is hemorrhoids he/she may prescribe something over the counter such as anusol.

External Hemorrhoids: First the etiology of the anal swelling must be determined. If it is a benign entity, such as hemorrhoids, then good bowel habits (i.e., not using the bathroom as a reading room--sitting for prolonged periods on the toilet), a high-fiber (greater than 30 g/day) low fat diet, and a minimum of 64 oz. Of water per day, should help prevent progression of the hemorrhoids and reduce swelling.