Sodium Thiosulfate
Sodium thiosulfate supports cyanide detoxification by supplying sulfur. Emergency treatment depends on exposure, oxygen delivery and the selected antidote protocol.
Group
Sulfur-donor antidote
Mechanism of Action
Provides sulfur for rhodanese-mediated conversion of cyanide to thiocyanate.
Dose Rates
Dogs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Cyanide antidote protocol | 413 mg/kg | IV | Protocol dose, not stand-alone prescription: slow IV after separately prescribed sodium nitrite with monitoring of oxygen delivery and methemoglobinemia. Complete antidote selection and timing must be specified. |
Cats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Cyanide antidote protocol | 413 mg/kg | IV | Protocol dose, not stand-alone prescription: slow IV after separately prescribed sodium nitrite with monitoring of oxygen delivery and methemoglobinemia. Complete antidote selection and timing must be specified. |
Cattle
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Cyanide antidote protocol | 413 mg/kg | IV | Protocol dose, not stand-alone prescription: slow IV after separately prescribed sodium nitrite with monitoring of oxygen delivery and methemoglobinemia. Complete antidote selection and timing must be specified. | |
| Alternative cyanide detoxification protocol | Reference only | IV | Described protocol uses sodium thiosulfate at least 500 mg/kg IV plus 30 g/cow PO for ongoing ruminal exposure. Select a complete emergency protocol; do not merge with the 413 mg/kg nitrite-following schedule. | |
| Ruminal cyanide detoxification adjunct | Reference only | PO | 30 g per cow orally has been described as an adjunct to the specified IV protocol. It does not replace systemic antidote therapy in a critically affected animal. | |
| Alternative cyanogenic-plant poisoning regimen | 660 mg/kg | IV | Once | Historical ruminant course using 30% solution. Rapid administration was described, while other instructions advise slow IV delivery; determine the actual rate in the complete emergency protocol before use. |
| Copper poisoning molybdate combination | Reference only | PO | Every 24 h | Up to 21 days; 500 mg sodium thiosulfate plus 200 mg ammonium or sodium molybdate total orally daily for up to 3 weeks, with fluid replacement. This is a fixed combination course, not an automatic single-active prescription. |
| Arsenic poisoning oral adjunct | Reference only | PO | Every 6 h | Up to 4 days; 30–60 g total every 6 hours for 3–4 days has been suggested, with fluid/electrolyte support; efficacy is uncertain. A separate IV amount of 30–60 g as a 10–20% solution was described without a repeat interval. |
Sheep
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Cyanide antidote protocol | 413 mg/kg | IV | Protocol dose, not stand-alone prescription: slow IV after separately prescribed sodium nitrite with monitoring of oxygen delivery and methemoglobinemia. Complete antidote selection and timing must be specified. | |
| Alternative cyanogenic-plant poisoning regimen | 660 mg/kg | IV | Once | Historical ruminant course using 30% solution. Rapid administration was described, while other instructions advise slow IV delivery; determine the actual rate in the complete emergency protocol before use. |
| Copper poisoning molybdate combination | Reference only | PO | Every 24 h | Up to 21 days; 500 mg sodium thiosulfate plus 200 mg ammonium or sodium molybdate total orally daily for up to 3 weeks, with fluid replacement. This is a fixed combination course, not an automatic single-active prescription. |
| Arsenic poisoning oral adjunct | Reference only | PO | Every 6 h | Up to 4 days; 30–60 g total every 6 hours for 3–4 days has been suggested, with fluid/electrolyte support; efficacy is uncertain. A separate IV amount of 30–60 g as a 10–20% solution was described without a repeat interval. |
Goats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Cyanide antidote protocol | 413 mg/kg | IV | Protocol dose, not stand-alone prescription: slow IV after separately prescribed sodium nitrite with monitoring of oxygen delivery and methemoglobinemia. Complete antidote selection and timing must be specified. | |
| Alternative cyanogenic-plant poisoning regimen | 660 mg/kg | IV | Once | Historical ruminant course using 30% solution. Rapid administration was described, while other instructions advise slow IV delivery; determine the actual rate in the complete emergency protocol before use. |
| Copper poisoning molybdate combination | Reference only | PO | Every 24 h | Up to 21 days; 500 mg sodium thiosulfate plus 200 mg ammonium or sodium molybdate total orally daily for up to 3 weeks, with fluid replacement. This is a fixed combination course, not an automatic single-active prescription. |
| Arsenic poisoning oral adjunct | Reference only | PO | Every 6 h | Up to 4 days; 30–60 g total every 6 hours for 3–4 days has been suggested, with fluid/electrolyte support; efficacy is uncertain. A separate IV amount of 30–60 g as a 10–20% solution was described without a repeat interval. |
Horses
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Arsenic poisoning adjunct | Reference only | PO | 20–30 g total in 300 mL water orally with dimercaprol 3 mg/kg IM q4h has been described. Evidence for arsenic benefit is uncertain; timing and hydration require a complete toxicology plan. | |
| Historical cyanide nitrite-following course | Reference only | IV | After sodium nitrite 16 mg/kg IV (another course uses 10–20 mg/kg IV as a 20% solution), give sodium thiosulfate 30–40 mg/kg IV as a 20% solution. If repeated, give thiosulfate alone. This historical amount is much lower than other cyanide courses; do not merge the ranges. |
Indications
- Cyanide poisoning within an emergency antidote protocol
Contraindications
- Hypersensitivity
Interactions
- Do not give hydroxocobalamin simultaneously through the same IV line because of chemical incompatibility.
- Do not run blood products and sodium thiosulfate simultaneously through the same IV line.
- Reported incompatibility with cyanocobalamin; do not admix.
Adverse effects
- Vomiting
- Hypotension with IV administration
- Profuse diarrhea after large oral doses
Toxicity
Excessive or rapid administration can disturb circulation and acid-base balance; monitor and provide supportive care.
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Sodium thiosulfate injection 25% w/v 250 mg/mL for the specified medicinal formulation. Select a complete cyanide antidote protocol; do not assume compatibility with other antidotes. | Injection | 250 mg / mL | IV |
| Sodium thiosulfate injection 10% w/v 100 mg/mL as pentahydrate; no assumed conversion to anhydrous salt. | Injection | 100 mg / mL | IV |
Monitoring and Administration
Provide airway, ventilation, oxygen and circulatory support while treating suspected cyanide exposure.
One veterinary protocol gives 413 mg/kg IV slowly after sodium nitrite. Another describes at least 500 mg/kg IV plus 30 g per cow orally to reduce ongoing ruminal cyanide release. These are different protocols and are not one broad dose range.
Nitrite use requires assessment of methemoglobinemia and oxygen delivery; some smoke-inhalation settings require a different antidote choice.
The older sheep study tested different thiosulfate/nitrite exposures; experimental doses are not substituted for a complete clinical protocol.
Monitor blood pressure and oxygenation. Store the described 250 mg/mL injection at 20–25°C, protected from light; do not freeze.
Large oral doses can cause profuse diarrhea. In arsenic or copper exposure, thiosulfate is an adjunct with uncertain arsenic efficacy; do not delay established poisoning management.
Human-derived extravasation approaches include a 2% SC solution with corticosteroids for anthracyclines, or 0.17 mol/L solution for cisplatin/carboplatin. A cited preparation combines 4 mL of 10% pentahydrate solution with 6 mL sterile water; 5 mL infiltration was described for carboplatin. These are not validated universal dog/cat protocols and must not be substituted for a drug-specific extravasation plan.
Historical ruminant withdrawal advice suggested 24 hours, but no current local authorization is inferred. Do not mix with cyanocobalamin; keep the already specified hydroxocobalamin incompatibility separate.