Sodium Thiosulfate

(rINNM)
Sodium Thiosulfate Chemical formula

💊 Chemical information

Disodium Thiosulfate Pentahydrate; Hiposulfito sódico; Natrii thiosulfas; Natrii Thiosulfas Pentahydricus; Natrio tiosulfatas; Natrium Thiosulfuricum; Natriumtiosulfaatti; Natriumtiosulfat; Nátrium-tioszulfát; Sodium Hyposulphite; Sodium, thiosulfate de; Sodium Thiosulphate; Sodu tiosiarczan; Sodyum Tiyosülfat; Thiosíran sodný pentahydrát; Tiosulfato sódico.
Chemical formula: Na2S2O3,5H2O = 248.2.
CAS — 7772-98-7 (anhydrous sodium thiosulfate); 10102-17-7 (sodium thiosulfate pentahydrate).
ATC — V0 3AB06.
ATC Vet — QV0 3AB06.

Pharmacopoeias.

In Chin., Eur., Int., Jpn, US, and Viet.

Ph. Eur. 6.2

(Sodium Thiosulphate). Colourless transparent crystals; efflorescent in dry air. It dissolves in its own water of crystallisation at about 49°. Very soluble in water; practically insoluble in alcohol. A 10% solution in water has a pH of 6.0 to 8.4. Store in airtight containers.

USP 31

(Sodium Thiosulfate). Large, colourless crystals, or a coarse, crystalline powder. Is deliquescent in moist air and effloresces in dry air at temperatures exceeding 33°. Soluble 1 in 0.5 of water; insoluble in alcohol. Its solutions are neutral or faintly alkaline to litmus. Store in airtight containers.

Incompatibility.

Sodium thiosulfate may reduce the activity of some preservatives, including bronopol, phenylmercuric salts, and thiomersal.

Stability.

Solutions of sodium thiosulfate 50% stored in air developed cloudiness or a deposit after autoclaving. 1 Addition of sodium phosphate 0.5% or 1.2% improved stability but solutions became cloudy or developed a deposit after 12 and 6 weeks respectively at 25°. Solutions containing sodium bicarbonate 0.5% became cloudy or developed a deposit after 12 weeks at 25°. No significant improvement in stability was obtained when the concentration of sodium thiosulfate was reduced to 30% or 15%, or when the injection was sealed under nitrogen. 1. Anonymous. Sodium thiosulphate injection–effect of additives on stability. PSGB Lab Rep P/75/3 1975.

💊 Adverse Effects

Apart from osmotic disturbances sodium thiosulfate is relatively non-toxic. Large oral doses have a cathartic action.

💊 Pharmacokinetics

Sodium thiosulfate is poorly absorbed from the gastrointestinal tract. After intravenous injection it is distributed throughout the extracellular fluid and rapidly excreted in the urine.
The thiosulfate was rapidly eliminated, 95% being excreted within 4 hours of stopping the infusion; on average only 28.5% of the dose was recovered unchanged in the urine. The mean plasma elimination half-life was 80 minutes.
1. Shea M, et al. Kinetics of sodium thiosulfate, a cisplatin neutralizer. Clin Pharmacol Ther 1984; 35: 419–25.

💊 Uses and Administration

Sodium thiosulfate is used in the treatment of cyanide poisoning. Sodium thiosulfate may be effective alone in less severe cases of cyanide poisoning, but it is often used with sodium nitrite. Sodium thiosulfate acts as a sulfur-donating substrate for the enzyme rhodanese, which catalyses the conversion of cyanide to relatively non-toxic thiocyanate, and thus accelerates the detoxification of cyanide. The usual dosage regimen in adults is 300 mg of sodium nitrite (10 mL of a 3% solution) given intravenously over 5 to 20 minutes followed by 12.5 g of sodium thiosulfate (50 mL of a 25% solution or 25 mL of a 50% solution) given intravenously over a period of about 10 minutes. A suggested dosage regimen in children is about 4 to 10 mg/kg of sodium nitrite, given as a 3% solution (0.13 to 0.33 mL/kg) to a maximum of 300 mg (10 mL), followed by about 400 mg/kg of sodium thiosulfate, as a 25 or 50% solution (1.65 mL/kg of a 25% solution) to a maximum of 12.5 g (50 mL of a 25% solution). The methaemoglobin concentration should not be allowed to exceed 30 to 40%. If symptoms of cyanide toxicity recur, the injections of nitrite and thiosulfate may be repeated after 30 minutes at half the initial doses. Sodium thiosulfate is used as an isotonic 4% solution in the management of extravasation of chlormethine and has been tried in the management of extravasation of some other antineoplastics (but see below). Sodium thiosulfate has been used for its antifungal properties. Sodium thiosulfate and magnesium thiosulfate are included in mixed preparations for a variety of disorders.

Antineoplastic toxicity.

Sodium thiosulfate may be used in the management of extravasation of chlormethine and some other antineoplastics. It is also used to inactivate some antineoplastics before disposal. Sodium thiosulfate, given by intravenous infusion, has also been investigated for reducing the systemic toxicity of some antineoplastics. It has been reported to reduce the incidence of nephrotoxicity associated with intraperitoneal cisplatin and to reduce hearing loss associated with carboplatin.

Bromate poisoning.

Sodium thiosulfate has been used in the treatment of bromate poisoning1,2 although its clinical efficacy is unclear;3 it is thought to act by reducing bromate to the less toxic bromide ion, but evidence is lacking.3,4 Although it has been given orally, this is no longer recommended since toxic sulfide may be formed.4 However, intravenous sodium thiosulfate may have a role in some clinical circumstances.4,5
1. Lue JN, et al. Bromate poisoning from ingestion of professional hair-care neutralizer. Clin Pharm 1988; 7: 66–70
2. Lichtenberg R, et al. Bromate poisoning. J Pediatr 1989; 114: 891–4
3. McElwee NE, Kearney TE. Sodium thiosulfate unproven as bromate antidote. Clin Pharm 1988; 7: 570, 572
4. De Vriese A, et al. Severe acute renal failure due to bromate intoxication: report of a case and discussion of management guidelines based on a review of the literature. Nephrol Dial Transplant 1997; 12: 204–9
5. Johnson CE. Sodium thiosulfate unproven as bromate antidote. Clin Pharm 1988; 7: 572.

💊 Preparations

BP 2008: Sodium Thiosulphate Injection; USP 31: Sodium Thiosulfate Injection. Proprietary PreparationsMulti-ingredient: Arg.: Azufracid; Austria: Schwefelbad Dr Klopfer; Braz.: Dessensibilizante Chauvin†; Canad.: Adasept; Cz.: Carbotox; Fr.: Desintex; Desintex Infantile; Desintex-Choline; Rhino-Sulfuryl; Vagostabyl; Ger.: Corti Jaikal†; Jaikal†; Schwefelbad Dr Klopfer; Sulfuretten†; Hung.: Schwefelbad Dr Klopfer; Ital.: Antimicotica Solforata; S.Afr.: Tripac-Cyano; USA: Cyanide Antidote Package; Tinver; Versiclear.
Published December 30, 2018.