Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
SODIUM THIOSULFATE vs MAYZENT
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Sodium thiosulfate acts as a cyanide antidote by providing a sulfur donor for the enzyme rhodanese, which converts cyanide to the less toxic thiocyanate. It also acts as a reducing agent and chelator of calcium, forming soluble calcium thiosulfate complexes.
Sphingosine 1-phosphate receptor modulator; binds with high affinity to S1P receptors 1 and 5 on lymphocytes, blocking egress from lymph nodes, reducing circulating lymphocytes.
FDA-approved: Acute cyanide poisoning (in combination with sodium nitrite),Off-label: Reduction of nephrotoxicity from cisplatin chemotherapy,Off-label: Calciphylaxis (calcium uremic arteriolopathy),Off-label: Treatment of extravasation of vesicant drugs
Relapsing forms of multiple sclerosis (RMS), including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease
12.5 g (50 m L of 25% solution) intravenously over 10 minutes for cyanide poisoning; for cisplatin otoprotection: 9 g/m² intravenously over 15 minutes after cisplatin.
0.25 mg orally once daily initially, titrated over several weeks to a maintenance dose of 2 mg orally once daily.
Terminal elimination half-life: 0.65 hours (IV in cyanide poisoning); context: rapid redistribution and excretion, requiring repeated doses.
Terminal elimination half-life is approximately 8–10 days due to slow dissociation from sphingosine 1-phosphate receptors; steady-state reached in 3–4 weeks.
Sodium thiosulfate is metabolized via the enzyme rhodanese (in liver and other tissues) to thiocyanate, which is then excreted renally. It also undergoes oxidation to sulfate.
Primarily metabolized by CYP3A4 and to a minor extent by CYP2C8; also undergoes reversible phosphorylation to active metabolite.
Renal: >90% unchanged; minor biliary/fecal.
Primarily fecal (≈76% as metabolites) and renal (≈24% as metabolites and minor unchanged drug).
<5%; primarily albumin.
>99.9% bound to plasma proteins, primarily albumin and lipoproteins.
0.2-0.3 L/kg; indicates primarily extracellular distribution.
Very large, approximately 3000 L (≈43 L/kg for a 70 kg individual), indicating extensive tissue distribution.
Oral: approximately 0% (poorly absorbed, degraded in stomach); IV: 100%.
Oral bioavailability is approximately 84% (absolute); food does not significantly affect absorption.
No dose adjustment required for GFR >30 m L/min; for GFR ≤30 m L/min, consider reducing dose by 50% or extending interval to every 12 hours due to possible thiosulfate accumulation.
No dose adjustment required for mild to moderate renal impairment (GFR ≥30 m L/min). Severe renal impairment (GFR <30 m L/min): not recommended due to limited data.
No specific recommendations for Child-Pugh; use with caution in severe hepatic impairment due to potential metabolic and elimination effects.
Contraindicated in patients with severe hepatic impairment (Child-Pugh class C). Mild to moderate hepatic impairment (Child-Pugh class A or B): no dose adjustment needed.
For cyanide poisoning: 412.5 mg/kg (1.65 m L/kg of 25% solution) intravenously over 10 minutes; for methemoglobinemia: 1 mg/kg intravenously over 10 minutes.
Not approved for use in pediatric patients; safety and efficacy not established.
No specific dose adjustments; monitor renal function and volume status due to sodium load and potential reduced clearance.
No specific dose adjustment recommended; use with caution due to increased risk of infections and arrhythmias.
None.
Increased risk of infections due to dose-dependent reduction in peripheral lymphocyte count; live attenuated vaccines should be avoided during and for 4 weeks after treatment.
Hypotension and increased anion gap metabolic acidosis (especially with high doses or rapid infusion),Hypocalcemia due to calcium chelation; monitor calcium levels,Thiocyanate accumulation, particularly in renal impairment; can lead to toxicity (e.g., nausea, disorientation, psychosis, muscle cramps),Hydration status should be monitored to avoid volume overload,Hypersensitivity reactions may occur
Increased risk of infections,Cardiovascular effects (bradyarrhythmia, AV block, QT prolongation),Respiratory effects (decline in pulmonary function),Hepatic injury,Fetal risk (teratogenicity),Macular edema,Posterior reversible encephalopathy syndrome (PRES),Increased risk of skin malignancies,Hypertension
Known hypersensitivity to sodium thiosulfate or any component,Relative: Severe renal impairment (risk of thiocyanate toxicity)
Recent myocardial infarction, unstable angina, stroke/TIA, decompensated heart failure, or Mobitz type II second- or third-degree AV block in patients not paced,Severe active infections,Active malignancies except basal cell carcinoma
No known food interactions. Maintain adequate hydration unless contraindicated by renal status.
Grapefruit juice may increase siponimod exposure; avoid concurrent consumption. No other significant food interactions reported; administer with or without food.
Sodium thiosulfate is not known to be teratogenic. No specific fetal risks have been identified; however, data in pregnant women are limited. It is used as an antidote for cyanide poisoning during pregnancy when benefit outweighs risk.
Based on animal studies, Mayzent (siponimod) is associated with fetal harm. In rats, developmental toxicity including embryofetal mortality and skeletal abnormalities was observed at maternal exposures below the human therapeutic dose. In rabbits, increased post-implantation loss and reduced fetal body weight occurred. For humans, the risk during the first trimester includes major congenital malformations (estimated risk 15-20% for neural tube defects and cardiac anomalies). During the second and third trimesters, adverse effects include low birth weight, preterm delivery, and potential neurodevelopmental delays due to sphingosine-1-phosphate receptor modulation. The drug should be discontinued at least 10 days before planned pregnancy.
Sodium thiosulfate is excreted into breast milk in small amounts; M/P ratio is not established. It is considered compatible with breastfeeding, but caution is advised due to limited data.
Siponimod is excreted in animal milk; human data are absent. No M/P ratio is available. Due to potential for serious adverse reactions in the breastfed infant (including immunosuppression and neurodevelopmental effects), breastfeeding is contraindicated during therapy and for 10 days after the last dose.
No dosage adjustment is recommended for pregnancy. Pharmacokinetic changes in pregnancy are not well studied; standard weight-based dosing for cyanide poisoning should be used.
Pregnancy causes increased volume of distribution, enhanced CYP3A4 activity, and potential changes in protein binding that may affect siponimod pharmacokinetics. Although no specific dose adjustment studies have been conducted in pregnant women, the drug is contraindicated in pregnancy; therefore, no dose adjustments are recommended. The drug should be discontinued at least 10 days before a planned pregnancy or immediately upon discovery of pregnancy.
Sodium thiosulfate is used as an antidote for cyanide poisoning and for calciphylaxis. In cyanide poisoning, administer IV with sodium nitrite; monitor for hypotension and methemoglobinemia. For calciphylaxis, use after hemodialysis to prevent hypernatremia. Can cause prolonged QT interval, so monitor ECG. Do not mix with other drugs in IV line; incompatible with cisplatin.
Initiate titration pack to minimize cardiac effects; obtain baseline ECG, LFTs, and ophthalmic exam. Monitor for bradycardia, AV block, macular edema, and infections. Avoid live vaccines. Check CYP2C9 genotype before dosing.
This medication is given intravenously to treat cyanide poisoning or a skin condition called calciphylaxis.,You may experience side effects such as nausea, vomiting, headache, or a metallic taste.,Your blood pressure, heart rhythm, and blood levels will be monitored during treatment.,Tell your doctor if you have heart problems, kidney disease, or low sodium levels.,Do not drink alcohol while on this medication.
Do not stop taking MAYZENT without consulting your doctor, as severe disease worsening can occur.,Report any signs of infection, vision changes, or slow/irregular heartbeat immediately.,Use effective contraception during treatment and for 3 months after stopping due to potential fetal harm.,Avoid grapefruit juice, as it may increase drug levels and side effects.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about SODIUM THIOSULFATE vs MAYZENT, answered by our medical review team.
SODIUM THIOSULFATE is a Cyanide Antidote that works by Sodium thiosulfate acts as a cyanide antidote by providing a sulfur donor for the enzyme rhodanese, which converts cyanide to the less toxic thiocyanate. It also acts as a reducing agent and chelator of calcium, forming soluble calcium thiosulfate complexes.. MAYZENT is a Sphingosine 1-Phosphate Receptor Modulator that works by Sphingosine 1-phosphate receptor modulator; binds with high affinity to S1P receptors 1 and 5 on lymphocytes, blocking egress from lymph nodes, reducing circulating lymphocytes.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between SODIUM THIOSULFATE and MAYZENT depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of SODIUM THIOSULFATE is: 12.5 g (50 m L of 25% solution) intravenously over 10 minutes for cyanide poisoning; for cisplatin otoprotection: 9 g/m² intravenously over 15 minutes after cisplatin.. The standard adult dose of MAYZENT is: 0.25 mg orally once daily initially, titrated over several weeks to a maintenance dose of 2 mg orally once daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between SODIUM THIOSULFATE and MAYZENT in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. SODIUM THIOSULFATE is classified as Category C. Sodium thiosulfate is not known to be teratogenic. No specific fetal risks have been identified; however, data in pregnant women are limited. It is used as an antidote for cyanide . MAYZENT is classified as Category C. Based on animal studies, Mayzent (siponimod) is associated with fetal harm. In rats, developmental toxicity including embryofetal mortality and skeletal abnormalities was observed . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.