[4][5] Other uses include topical treatment of ringworm and tinea versicolor,[3][6] and treating some side effects of hemodialysis[7] and chemotherapy.

[8][9] In September 2022, the U.S. Food and Drug Administration (FDA) approved sodium thiosulfate under the trade name Pedmark to lessen the risk of ototoxicity and hearing loss in infant, child, and adolescent cancer patients receiving the chemotherapy medication cisplatin.

[10][11] In photography, sodium thiosulfate is used in both film and photographic paper processing as a fixer, sometimes still called 'hypo' from the original chemical name, hyposulphite of soda.

The S-S distance indicates a single bond, implying that the terminal sulfur holds a significant negative charge and the S-O interactions have more double-bond character.

[13] This salt can also be prepared by boiling aqueous sodium hydroxide and sulfur according to the following equation.

[14][15] However, this is not recommended outside of a laboratory, as exposure to hydrogen sulfide can result if improperly handled.

Under normal conditions, acidification of solutions of this salt excess with even dilute acids results in complete decomposition to sulfur, sulfur dioxide, and water:[13] Thiosulfate forms complexes with transition metal ions.

This reaction is illustrated by one synthesis of thioglycolic acid: Sodium thiosulfate has low toxicity.