Used in medicine to treat cyanide poisoning by converting cyanide into less toxic thiocyanate, which is then excreted in urine. Commonly employed in emergency settings, often alongside sodium nitrite. Also used in dermatology to treat certain skin conditions like pityriasis versicolor. In industrial settings, serves as a dechlorinating agent to neutralize chlorine in water treatment and aquarium systems. Widely used in photography as a fixing agent to dissolve unexposed silver halides from photographic film and paper. Applied in analytical chemistry as a titrant in iodometric titrations to determine oxidizing agents. Also utilized in textile, paper, and leather industries for bleaching and desulfurization processes.