A tablet-formed pharmaceutical composition for oral administration consisting of 65 % or more by weight of a spherical activated carbon as an active ingredient, and one or more excipients; wherein (a) the spherical activated carbon does not exhibit a water solubility and a swelling characteristic; a distortion rate thereof is 2 % or less when 2 MPa of pressure is applied; and a fracture strength thereof is 5 MPa or more; (b) the tablet-formed pharmaceutical composition for oral administration comprises one or more excipients for tablet formulation selected from the group consisting of pullulan, polyvinyl alcohol, gelatin, povidone, pregelatinized starch, oxidized starch, hypromellose, hydroxypropyl starch, dextrin, polyvinyl alcohol-acrylic acid-methyl methacrylate copolymer, Kanbaiko, propylene glycol alginate, agar, glucomannan, carmellose sodium, hydroxyethylcellulose, hydroxypropylcellulose, tara gum, tamarind gum, carrageenan, methylcellulose, sodium hyaluronate, sodium alginate, carboxyvinyl polymer, partly pregelatinized starch, tragacanth, guar gum, xanthan gum, quince seed gum, locust bean gum, distarch phosphate, ghatti gum, and gellan gum, wherein the amount of the excipients for tablet formulation totals 1 % or more by weight with respect to the tablet-formed pharmaceutical composition for oral administration, provided that when the excipients for tablet formulation include pullulan, the amount of pullulan is 1 % or more by weight with respect to the tablet-formed pharmaceutical composition for oral administration, and the excipient for tablet formulation forms a thin film when 0.5 mL of a water solution or a water dispersion of the excipient for tablet formulation of 1 % by weight is heat-dried after being placed on a flat surface made of fluorine resin wherein the distortion rate is determined as referred in the description. (a) the spherical activated carbon does not exhibit a water solubility and a swelling characteristic; a distortion rate thereof is 2 % or less when 2 MPa of pressure is applied; and a fracture strength thereof is 5 MPa or more; (b) the tablet-formed pharmaceutical composition for oral administration comprises one or more excipients for tablet formulation selected from the group consisting of pullulan, polyvinyl alcohol, gelatin, povidone, pregelatinized starch, oxidized starch, hypromellose, hydroxypropyl starch, dextrin, polyvinyl alcohol-acrylic acid-methyl methacrylate copolymer, Kanbaiko, propylene glycol alginate, agar, glucomannan, carmellose sodium, hydroxyethylcellulose, hydroxypropylcellulose, tara gum, tamarind gum, carrageenan, methylcellulose, sodium hyaluronate, sodium alginate, carboxyvinyl polymer, partly pregelatinized starch, tragacanth, guar gum, xanthan gum, quince seed gum, locust bean gum, distarch phosphate, ghatti gum, and gellan gum, wherein the amount of the excipients for tablet formulation totals 1 % or more by weight with respect to the tablet-formed pharmaceutical composition for oral administration, provided that when the excipients for tablet formulation include pullulan, the amount of pullulan is 1 % or more by weight with respect to the tablet-formed pharmaceutical composition for oral administration, and the excipient for tablet formulation forms a thin film when 0.5 mL of a water solution or a water dispersion of the excipient for tablet formulation of 1 % by weight is heat-dried after being placed on a flat surface made of fluorine resin wherein the distortion rate is determined as referred in the description.