Sodium thiosulfate is indicated to treat serious or life-threatening acute cyanide poisoning and for the prevention of cisplatin-related ototoxicity in pediatric patients older than 1 month of age; it may not reduce the risk of ototoxicity with cisplatin infusions longer than 6 hours, as irreversible ototoxicity may have already occurred. When used for ototoxicity prophylaxis, it must be separated from cisplatin administration by 6 to 10 hours due to decreased cytotoxicity of cisplatin to tumor cells. For treatment of cyanide poisoning, sodium thiosulfate is used sequentially (immediately after) sodium nitrite. Administer treatment without delay if clinical suspicion of cyanide poisoning is high; however, in cases where the diagnosis is uncertain, the potential risks associated with treatment should be carefully weighed against the potential benefits. For expert advice, contact Poison Control at 1-800-222-1222 or online.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Injectable Administration
-Ensure the correct product is used for the intended indication.
-Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.
Intravenous Administration
Cyanide antidote
NOTE: When treating acute cyanide intoxication, sodium nitrite and sodium thiosulfate should be considered as adjunctive therapies to appropriate support of vital functions. Do not delay airway, ventilatory, and circulatory support or oxygenation in order to administer sodium nitrite and sodium thiosulfate.
NOTE: For expert advice, contact Poison Control at 1-800-222-1222 or online.
-Withdraw the contents of 1 vial (50 mL) into a suitable syringe.
-Immediately after giving sodium nitrite, administer sodium thiosulfate by slow intravenous injection while monitoring blood pressure. Slow the injection rate if significant hypotension is noted. Sodium nitrite and sodium thiosulfate may be administered sequentially through the same IV line, as no chemical incompatibilities have been reported.
-DO NOT administer concurrently in the same IV line with other cyanide antidotes, hydroxocobalamin, or blood products (whole blood, packed red cells, platelet concentrate or fresh frozen plasma). However, sodium thiosulfate may be administered simultaneously with blood products if using separate IV lines (preferably on contralateral extremities, if using peripheral lines).
-Observe patient closely for at least 24 to 48 hours. If signs of poisoning reappear, injections of sodium nitrite and sodium thiosulfate may be repeated at one-half of the original dose.
Ototoxicity prophylaxis (PEDMARK)
-Administer antiemetics before each infusion.
-For patients who have had a hypersensitivity reaction, administer antihistamines and glucocorticoids (if applicable) prior to each subsequent dose.
Preparation (PEDMARK):
-Withdraw the calculated dose from the vial into a syringe or transfer it to an empty infusion bag.
-Storage after preparation: Use immediately. If unable to use immediately, it can be stored in an infusion bag for no more than 18 hours at 68 to 72 degrees F (20 to 22 degrees C). Discard unused portion.
Intravenous injection (PEDMARK):
-Administer as an IV infusion over 15 minutes.
Intramuscular Administration
Reconstitution:
-A 1/6 M solution should be prepared by mixing 4 mL of sodium thiosulfate 10% w/v with 6 mL sterile water for injection.
Intramuscular injection:
-Inject the prepared solution intramuscularly into the site of extravasation.
Subcutaneous Administration
Reconstitution:
-A 1/6 M solution should be prepared by mixing 4 mL of sodium thiosulfate 10% w/v with 6 mL sterile water for injection.
Subcutaneous injection:
-Inject the prepared solution subcutaneously into the site of extravasation.
Other Injectable Administration
Intradermal administration
Reconstitution:
-A 1/6 M solution should be prepared by mixing 4 mL of sodium thiosulfate 10% w/v with 6 mL sterile water for injection.
Intradermal injection:
-Inject the prepared solution intradermally into the site of extravasation.
Hypotension has been reported with sodium thiosulfate use. Sodium thiosulfate is recommended to be administered via slow IV injection for acute cyanide poisoning to help limit hypotension. Hypertension was also reported in postmarketing experience with sodium thiosulfate for the prevention of cisplatin-related ototoxicity.
Headache and disorientation or confusion have been reported with sodium thiosulfate use.
Nausea occurred in 40% of pediatric patients receiving sodium thiosulfate for the prevention of cisplatin-related ototoxicity compared with 30% of those receiving cisplatin without sodium thiosulfate (grade 3 or 4, 3.8% vs. 5%); sodium thiosulfate was administered either 6 hours after or 10 hours before cisplatin. Vomiting occurred in 85% versus 54% (grade 3 or 4, 8% vs. 3.6%) of patients in this trial, respectively. Administer antiemetics prior to each administration of prophylactic sodium thiosulfate. A higher incidence of nausea and vomiting occurs with rapid administration of concentrated solutions or solutions that were not freshly prepared and with the administration of larger doses. Severe (grade 3 or 4) stomatitis was also reported in 14% of pediatric patients receiving sodium thiosulfate for prophylaxis of cisplatin-related ototoxicity compared with 6% of those who received cisplatin without sodium thiosulfate.
Sodium thiosulfate use has been associated with prolonged bleeding time. Of eleven patients that received a single IV infusion of 50 mL sodium thiosulfate, 50% experienced increases in clotting time 1 to 3 days after administration. No significant changes were observed in other hematological parameters.
Reports of a salty taste in the mouth (dysgeusia) and a warm sensation over the body have been reported with sodium thiosulfate use.
Hypernatremia occurred in 12% to 26% of patients receiving sodium thiosulfate for the prophylaxis of cisplatin-induced ototoxicity (grade 3 or 4, 1.9% or less) compared with 3.6% to 6% of those receiving cisplatin without sodium thiosulfate (grade 3 or 4, 0%). Do not begin prophylaxis in patients with a baseline serum sodium greater than 145 mmol/L; additionally, interrupt prophylaxis in patients who develop a serum sodium level greater than 145 mmol/L during therapy. Additionally, hypokalemia occurred in 15% to 27% (grade 3 or 4, 9% to 27%) of patients who received sodium thiosulfate prophylaxis compared with 1.8% to 20% of those receiving cisplatin alone (grade 3 or 4, 20% or less). An interruption of prophylaxis is also necessary for patients with grade 3 or 4 hypokalemia. Monitor sodium and potassium levels at baseline and as clinically indicated for patients receiving sodium thiosulfate as ototoxicity prophylaxis. Hypophosphatemia (15% to 20%; grade 3 or 4, 9% to 20%), hyponatremia (14% or less; grade 3 or 4, 12% or less), and hypermagnesemia (11% or less; grade 3 or 4, 9% or less) have also occurred. Metabolic acidosis and hypocalcemia were reported in postmarketing experience. In a randomized clinical trial, the recommended dose of sodium thiosulfate for ototoxicity prophylaxis resulted in an average transient increase in serum sodium levels of approximately 6 mmol/L at 1 hour after infusion; levels returned to baseline by 18 to 24 hours after administration.
Sodium thiosulfate may contain sodium sulfite or trace impurities of sodium sulfite which can cause hypersensitivity reactions, including anaphylactoid reactions and life-threatening or severe asthma episodes in patients with sulfite sensitivity. Hypersensitivity reactions occurred in 8% to 13% of pediatric patients in clinical trials using sodium thiosulfate for the prevention of cisplatin-related ototoxicity. Monitor patients for hypersensitivity reactions. Immediately discontinue sodium thiosulfate for ototoxicity prophylaxis and administer appropriate supportive care if a hypersensitivity reaction occurs; permanently discontinue sodium thiosulfate for ototoxicity prophylaxis if a grade 3 or 4 hypersensitivity reaction occurs. For grade 1 or 2 hypersensitivity reactions, administer antihistamines or glucocorticoids (if appropriate) prior to each subsequent administration of sodium thiosulfate for ototoxicity prophylaxis.
Decreased hemoglobin (anemia) occurred in 34% of pediatric patients who received sodium thiosulfate for prevention of cisplatin-related ototoxicity compared with 29% of those who received cisplatin without sodium thiosulfate in a randomized clinical trial (grade 3 or 4, 19% vs. 16%).
Fever occurred in 15% of pediatric patients who received sodium thiosulfate for prevention of cisplatin-related ototoxicity compared with 9% of those who received cisplatin without sodium thiosulfate in a randomized clinical trial.
Monitor hemodynamics closely during and after treatment with sodium thiosulfate, and infusion rates of the drug should be slowed if hypotension occurs.
The use of sodium thiosulfate for the prophylaxis of cisplatin-induced ototoxicity has been associated with hypernatremia and hypokalemia. Do not begin prophylaxis in patients with a baseline serum sodium greater than 145 mmol/L; additionally, interrupt prophylaxis in patients who develop a serum sodium level greater than 145 mmol/L during therapy. Monitor sodium and potassium levels at baseline and as clinically indicated. Monitor for signs and symptoms of hypernatremia and hypokalemia; provide supportive care and supplementation as appropriate. Because sodium thiosulfate is renally excreted, monitor more closely in patients with renal impairment (GFR less than 60 mL/min/1.73m2); no dose adjustments are recommended. The sodium load of a 20 g/m2 dose, 15 g/m2 dose, and 10 g/m2 dose of sodium thiosulfate is 162 mmol/m2, 121 mmol/m2, and 81 mmol/m2, respectively. Pediatric patients younger than 1 month of age have less well-developed sodium homeostasis compared to other pediatric patients; sodium thiosulfate is not recommended for ototoxicity prophylaxis in pediatric patients younger than 1 month of age.
Use sodium thiosulfate for the prophylaxis of cisplatin-related ototoxicity with caution in patients with sulfite hypersensitivity. Monitor patients for hypersensitivity reactions. Immediately discontinue sodium thiosulfate for ototoxicity prophylaxis and administer appropriate supportive care if a hypersensitivity reaction occurs; permanently discontinue sodium thiosulfate for ototoxicity prophylaxis if a grade 3 or 4 hypersensitivity reaction occurs. For grade 1 or 2 hypersensitivity reactions, administer antihistamines or glucocorticoids (if appropriate) prior to each subsequent administration of sodium thiosulfate for ototoxicity prophylaxis. Sodium thiosulfate may contain sodium sulfite or trace impurities of sodium sulfite which can cause hypersensitivity reactions, including anaphylactic symptoms and life-threatening or severe asthma episodes in patients with sulfite sensitivity. The overall prevalence of sulfite sensitivity in the general population is unknown, but sulfite sensitivity is seen more frequently in people with asthma compared to people without asthma. The presence of trace amounts of sulfites in this product should not deter administration of the drug for emergency treatment, even if the patient is sulfite-sensitive.
The safety and efficacy of sodium thiosulfate has not been established in neonates and infants when used for acute cyanide toxicity. Additionally, the safety and efficacy of sodium thiosulfate has not been established for the prevention of cisplatin-related ototoxicity in pediatric patients younger than 1 month of age or in pediatric patients with metastatic cancer. Pediatric patients younger than 1 month of age have less well-developed sodium homeostasis compared to other pediatric patients; due to the risk of hypernatremia, sodium thiosulfate is not recommended for ototoxicity prophylaxis in pediatric patients younger than 1 month of age.
There are no data available regarding sodium thiosulfate use during pregnancy to establish a drug-associated risk for major birth defects, miscarriages, or adverse maternal or fetal outcomes. However, because cyanide poisoning can be fatal to a pregnant woman and the fetus if left untreated, it is recommended that treatment not be withheld for that indication due to pregnancy. In animal studies, sodium thiosulfate administered orally was not embryotoxic or teratogenic when administered during organogenesis to pregnant mice, rats, hamsters, and rabbits. The doses administered ranged from 0.2- to 0.9-times the human dose for cyanide toxicity and 0.08- to 0.35-times the highest dose for ototoxicity prophylaxis based on body surface area. Due to poor oral bioavailability, exposure in these animals compared to humans may be much lower. Additionally, sodium thiosulfate did not cross the placenta in an IV pharmacokinetic study in gravid ewes.
There are no data available regarding the presence of sodium thiosulfate in human milk, the effects on a breast-fed infant, or the effects on milk production. Cyanide and thiocyanate (which is formed when sodium thiosulfate combines with cyanide) are excreted in human milk. Due to the potential for serious adverse reactions in a nursing infant, breast-feeding is not recommended during treatment with sodium thiosulfate. It has not been determined when breast-feeding may be safely restarted following drug administration. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, healthcare providers are encouraged to report the adverse effect to the FDA.
Per the manufacturer, this drug has been shown to be active against most strains of the following microorganisms either in vitro and/or in clinical infections: Malassezia furfur
NOTE: The safety and effectiveness in treating clinical infections due to organisms with in vitro data only have not been established in adequate and well-controlled clinical trials.
For sequential use with sodium nitrite for the treatment of acute cyanide toxicity that is deemed serious or life-threatening:
NOTE: There is no widely available, rapid, confirmatory cyanide blood test; therefore, treatment decision must be made based on clinical history and signs and symptoms of cyanide intoxication.
NOTE: Sources of cyanide poisoning include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, exposure to fire or smoke from an enclosed area, and prolonged exposure to sodium nitroprusside.
Intravenous dosage:
Adults: 12.5 g (50 mL) by slow IV injection immediately after sodium nitrite. Monitor blood pressure during the injection; decrease injection rate if significant hypotension is noted. Closely monitor patients for 24 to 48 hours for recurrent symptoms of cyanide poisoning. If symptoms return, repeat treatment with both sodium nitrite and sodium thiosulfate at one-half the original doses. For expert advice, contact Poison Control at 1-800-222-1222; DO NOT delay treatment if cyanide poisoning is suspected.
Children and Adolescents: 250 mg/kg (1 mL/kg or 30 to 40 mL/m2) by slow IV injection immediately after sodium nitrite; maximum dosage is 12.5 g (50 mL). Monitor blood pressure during the injection; decrease injection rate if significant hypotension is noted. Closely monitor patients for 24 to 48 hours for recurrent symptoms of cyanide poisoning. If symptoms return, repeat treatment with both sodium nitrite and sodium thiosulfate at one-half the original doses. For expert advice, contact Poison Control at 1-800-222-1222; DO NOT delay treatment if cyanide poisoning is suspected.
For the treatment of extravasation* of cytotoxic drugs (e.g., cisplatin, dacarbazine, mechlorethamine, mustine):
Extravasation site dosage:
Adults: A 1/6 M solution should be prepared by mixing 4 mL of sodium thiosulfate 10% with 6 mL sterile water for injection. Inject the prepared solution into the site of extravasation.
Neonates, Infants, Children, and Adolescents: Use not recommended.
For the treatment of calciphylaxis* in patients undergoing dialysis:
Intravenous dosage:
Adults: 25 g in 100 mL 0.9% Sodium Chloride injection IV given 3 times per week over 30 to 60 minutes after hemodialysis or in peritoneal dialysis patients or during the last 30 minutes of hemodialysis.
For ototoxicity prophylaxis associated with cisplatin treatment in pediatric patients 1 month of age or older with localized, nonmetastatic solid tumors:
NOTE: Sodium thiosulfate may not reduce the risk of ototoxicity following longer cisplatin infusions as irreversible ototoxicity may have already occurred. The safety and efficacy of sodium thiosulfate have not been established following cisplatin infusions longer than 6 hours.
Intravenous dosage:
Infants, Children, and Adolescents weighing more than 10 kg: 20 grams/m2 IV over 15 minutes. Administer 6 hours after completion of a cisplatin infusion; for multiday cisplatin regimens, administer sodium thiosulfate 6 hours after completion of each cisplatin infusion and at least 10 hours before the next cisplatin infusion. If the next cisplatin infusion is scheduled to begin in less than 10 hours, do not administer sodium thiosulfate. Do not substitute sodium thiosulfate (Pedmark) with other sodium thiosulfate products. In a multicenter, randomized, open label, phase 3 trial (SIOPEL 6), 114 pediatric patients (age 1 month to 18 years) receiving cisplatin-based chemotherapy for standard risk hepatoblastoma were randomized to receive treatment with or without sodium thiosulfate. After 6 cycles of chemotherapy, 39% of patients receiving cisplatin plus sodium thiosulfate experienced hearing loss compared with 68% of those receiving cisplatin alone. In another multicenter, randomized, open-label phase 3 trial (COG ACCL0431), 125 pediatric patients (ages 1 to 18 years) receiving a chemotherapy regimen containing a cumulative cisplatin dose of at least 200 mg/m2 were randomized to cisplatin alone or with sodium thiosulfate; forty-four percent of patients who received sodium thiosulfate experienced hearing loss compared with 58% of those who did not.
Infants weighing 5 to 10 kg: 15 grams/m2 IV over 15 minutes. Administer 6 hours after completion of a cisplatin infusion; for multiday cisplatin regimens, administer sodium thiosulfate 6 hours after completion of each cisplatin infusion and at least 10 hours before the next cisplatin infusion. If the next cisplatin infusion is scheduled to begin in less than 10 hours, do not administer sodium thiosulfate. Do not substitute sodium thiosulfate (Pedmark) with other sodium thiosulfate products. In a multicenter, randomized, open label, phase 3 trial (SIOPEL 6), 114 pediatric patients (age 1 month to 18 years) receiving cisplatin-based chemotherapy for standard risk hepatoblastoma were randomized to receive treatment with or without sodium thiosulfate. After 6 cycles of chemotherapy, 39% of patients receiving cisplatin plus sodium thiosulfate experienced hearing loss compared with 68% of those receiving cisplatin alone. In another multicenter, randomized, open-label phase 3 trial (COG ACCL0431), 125 pediatric patients (ages 1 to 18 years) receiving a chemotherapy regimen containing a cumulative cisplatin dose of at least 200 mg/m2 were randomized to cisplatin alone or with sodium thiosulfate; forty-four percent of patients who received sodium thiosulfate experienced hearing loss compared with 58% of those who did not.
Infants weighing less than 5 kg: 10 grams/m2 IV over 15 minutes. Administer 6 hours after completion of a cisplatin infusion; for multiday cisplatin regimens, administer sodium thiosulfate 6 hours after completion of each cisplatin infusion and at least 10 hours before the next cisplatin infusion. If the next cisplatin infusion is scheduled to begin in less than 10 hours, do not administer sodium thiosulfate. Do not substitute sodium thiosulfate (Pedmark) with other sodium thiosulfate products. In a multicenter, randomized, open label, phase 3 trial (SIOPEL 6), 114 pediatric patients (age 1 month to 18 years) receiving cisplatin-based chemotherapy for standard risk hepatoblastoma were randomized to receive treatment with or without sodium thiosulfate. After 6 cycles of chemotherapy, 39% of patients receiving cisplatin plus sodium thiosulfate experienced hearing loss compared with 68% of those receiving cisplatin alone. In another multicenter, randomized, open-label phase 3 trial (COG ACCL0431), 125 pediatric patients (ages 1 to 18 years) receiving a chemotherapy regimen containing a cumulative cisplatin dose of at least 200 mg/m2 were randomized to cisplatin alone or with sodium thiosulfate; forty-four percent of patients who received sodium thiosulfate experienced hearing loss compared with 58% of those who did not.
Therapeutic Drug Monitoring:
Dosage Adjustments for Treatment-Related Toxicities (PEDMARK)
Electrolyte Abnormalities
-Hypernatremia (sodium greater than 145 mmol/L): Hold sodium thiosulfate. When sodium level is within normal limits, resume sodium thiosulfate at the same dose.
-Hypokalemia (grade 3 or 4): Hold sodium thiosulfate. When potassium level is within normal limits, resume sodium thiosulfate at the same dose.
Hypersensitivity
-Grade 3 or 4: Permanently discontinue sodium thiosulfate.
Other Adverse Reactions
-Grade 3: Hold sodium thiosulfate. When the adverse reaction resolves to grade 1 or less, resume sodium thiosulfate at the same dose.
-Grade 4: Permanently discontinue sodium thiosulfate.
Maximum Dosage Limits:
-Adults
12.5 g (50 mL) per dose IV for cyanide toxicity; safety and efficacy not established for ototoxicity prophylaxis.
-Geriatric
12.5 g (50 mL) per dose IV for cyanide toxicity; safety and efficacy not established for ototoxicity prophylaxis.
-Adolescents
12.5 g (50 mL) per dose IV for cyanide toxicity.
more than 10 kg: 20 g/m2 IV for ototoxicity prophylaxis.
-Children
12.5 g (50 mL) per dose IV for cyanide toxicity.
more than 10 kg: 20 g/m2 IV for ototoxicity prophylaxis.
5 to 10 kg: 15 g/m2 for IV ototoxicity prophylaxis.
-Infants
1 month of age and older and 5 to 10 kg: 15 g/m2 IV for ototoxicity prophylaxis.
1 month of age and older and less than 5 kg: 10 g/m2 IV for ototoxicity prophylaxis.
Safety and efficacy not established for cyanide toxicity.
-Neonates
Safety and efficacy have not been established.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
There are no drug interactions associated with Sodium Thiosulfate products.
Treatment of cyanide poisoning: Acts as a sulfur-donating substrate for rhodanase, an enzyme which is found mainly in the liver. Rhodanase catalyzes the conversion of cyanide to relatively nontoxic thiocyanate which can be safely excreted in the urine. By providing extra sulfur and increasing the rate of reaction of rhodanase, sodium thiosulfate accelerates the detoxification of cyanide. In animal studies, pretreatment with sodium thiosulfate increased the conversion rate of cyanide to thiocyanate by over 30-fold.
Prevention of cisplatin-induced ototoxicity: Cisplatin-induced ototoxicity is caused by irreversible damage to hair cells in the cochlea hypothesized to be due to a combination of reactive oxygen species (ROS) production and direct alkylation of DNA leading to cell death. Sodium thiosulfate reduces the risk of ototoxicity by interacting directly with cisplatin to produce an inactive platinum species and by entering cells via a sodium sulfate cotransporter 2, increasing levels of the antioxidant glutathione and inhibiting intracellular oxidative stress. Concurrent incubation of sodium thiosulfate with cisplatin decreased the in vitro cytotoxicity of cisplatin to tumor cells; delaying the addition of sodium thiosulfate to these cultures prevented this effect.
Extravasation management: Provides a substrate for alkylating agents that have invaded skin tissue which helps prevents alkylation and tissue destruction.
Sodium thiosulfate is administered intravenously, intradermally, intramuscularly, and subcutaneously. Once in the systemic circulation, sodium thiosulfate is distributed into extracellular fluid. Thiosulfate is an endogenous intermediate product of sulfur-containing amino acid metabolism. It is metabolized through thiosulfate sulfur transferase and thiosulfate reductase to sulfate, which is subsequently oxidized to sulfate; thiosulfate may also be incorporated into endogenous sulfur compounds. Approximately 20% to 50% of the thiosulfate dose is excreted unchanged in the urine. The serum thiosulfate half-life is reported to be 20 minutes following a 1 g intravenous dose; however, the half-life was reported as 182 minutes after the administration of a larger dose (150 mg/kg or 9 g for 60 kg body weight). After detoxification, thiocyanate is excreted in the urine at a rate inversely proportional to creatinine clearance; in healthy subjects, the volume of distribution and half-life of thiocyanate is 0.25 L/kg and 2.7 days, respectively.
Affected cytochrome P450 (CYP) enzymes and drug transporters: CYP2B6
Sodium thiosulfate induces CYP2B6 in vitro.
-Route-Specific Pharmacokinetics
Oral Route
Sodium thiosulfate is not systemically absorbed following oral administration.
Intramuscular Route
Pharmacokinetic data on the absorption of sodium thiosulfate following intramuscular administration are unknown.
Subcutaneous Route
Pharmacokinetic data on the absorption of sodium thiosulfate following subcutaneous administration are unknown.
Other Route(s)
Intradermal Route
Pharmacokinetic data on the absorption of sodium thiosulfate following intradermal administration are unknown.
-Special Populations
Renal Impairment
Compared to healthy subjects, the elimination half-life of thiocyanate in patients with renal insufficiency is prolonged to approximately 9 days. The thiosulfate Cmax and AUC increased by approximately 25% and 2-fold, respectively, in pediatric subjects on hemodialysis (GFR 0 to 6 mL/min/1.72 m2, estimated by MDRD) compared to subjects with normal renal function (GFR greater than 70 mL/min/1.72 m2, MDRD).
Pediatrics
The mean Cmax of thiosulfate in pediatric patients at the recommended dose for ototoxicity prophylaxis was 13 mmol (+/- 1.2 mmol); the Cmax increased in a dose proportional manner over the range of 4 g/m2 to 20 g/m2. Thiosulfate accumulation is not expected for the 2 days following administration of sodium thiosulfate. The mean volume of distribution was 0.23 L/kg. The mean half-life of thiosulfate is approximately 20 minutes to 50 minutes in pediatric patients, with a clearance of 2.2 mL/min/kg in patients with fully developed renal function (age approximately 1 year); renal clearance accounts for about 50% of total clearance in these patients. Approximately 50% of the administered sodium thiosulfate was excreted unchanged in urine, with more than 95% excreted in the first 4 hours after administration.