A capsule for use in treating ulcerative colitis, which capsule disintegrates locally in the large intestine, and comprises a drug-containing content, a protective layer coating the content and a film formed outside the protective layer, and which layers are arranged concentrically, wherein the content is a content in which indigo is dispersed or dissolved, the indigo being an active ingredient for treating ulcerative colitis, the protective layer contains an oily substance, wherein the oily substance is comprising one or a mixture of at least two selected from edible hardened oil and fat, a sucrose fatty acid ester, and a glycerin fatty acid ester, the film is a film which chitosan powder is dispersed in a film base material of a natural water-soluble polymer, and the natural water-soluble polymer is a mixture of a first natural water-soluble polymer and a second natural water-soluble polymer, the first natural water-soluble polymer is composed of one or a mixture of at least two selected from the group consisting of gelatin, carrageenan, starch, agar, pullulan, modified starch, alginic acid and mannan, and the second natural water-soluble polymer is composed of one or a mixture of at least two selected from the group consisting of pectin, gellan gum and curdlan, wherein the drug-containing content, the protective layer, the film, or a combination thereof further contains an adherable substance to an epithelial of large intestine, a substance increasing residence time in the large intestine or a combination thereof, wherein the adherable substance to the epithelial of large intestine is selected from fat-soluble tocopherol, mucus glycoprotein mucin, polyphosphoric acid, carboxyvinyl polymer, poly-N-vinyl acetamide, polyvinyl alcohol, acrylic acid/acrylic acid octyl copolymer, silk-fibroin acrylate copolymer resin, methacrylic acid/acrylic acid n-butyl copolymer, polyacrylic acid/acrylic acid octyl ester copolymer, acrylic acid-2-ethylhexyl/vinylpyrrolidone copolymer, methyl acrylate/acrylic acid-2-ethylhexyl copolymer resin, polyisoprene, polyacrylic acid and sodium polyacrylate, and rubbers, and wherein the capsule is configured to disintegrate locally in large intestine of a subject to whom the capsule is administered to release the indigo. the content is a content in which indigo is dispersed or dissolved, the indigo being an active ingredient for treating ulcerative colitis, the protective layer contains an oily substance, wherein the oily substance is comprising one or a mixture of at least two selected from edible hardened oil and fat, a sucrose fatty acid ester, and a glycerin fatty acid ester, the film is a film which chitosan powder is dispersed in a film base material of a natural water-soluble polymer, and the natural water-soluble polymer is a mixture of a first natural water-soluble polymer and a second natural water-soluble polymer, the first natural water-soluble polymer is composed of one or a mixture of at least two selected from the group consisting of gelatin, carrageenan, starch, agar, pullulan, modified starch, alginic acid and mannan, and the second natural water-soluble polymer is composed of one or a mixture of at least two selected from the group consisting of pectin, gellan gum and curdlan, wherein the drug-containing content, the protective layer, the film, or a combination thereof further contains an adherable substance to an epithelial of large intestine, a substance increasing residence time in the large intestine or a combination thereof, wherein the adherable substance to the epithelial of large intestine is selected from fat-soluble tocopherol, mucus glycoprotein mucin, polyphosphoric acid, carboxyvinyl polymer, poly-N-vinyl acetamide, polyvinyl alcohol, acrylic acid/acrylic acid octyl copolymer, silk-fibroin acrylate copolymer resin, methacrylic acid/acrylic acid n-butyl copolymer, polyacrylic acid/acrylic acid octyl ester copolymer, acrylic acid-2-ethylhexyl/vinylpyrrolidone copolymer, methyl acrylate/acrylic acid-2-ethylhexyl copolymer resin, polyisoprene, polyacrylic acid and sodium polyacrylate, and rubbers, and wherein the capsule is configured to disintegrate locally in large intestine of a subject to whom the capsule is administered to release the indigo.