Nithiodote Sodium Thiosulfate and Sodium Nitrite

Sodium thiosulfate and sodium nitrite are used to treat cyanide poisoning.

Sodium thiosulfate and sodium nitrite are available under the following different brand names: Nithiodote.

Dosing Form and Strengths

Kit

• sodium thiosulfate injection: 250mg/mL (12.5g/50mL vial) 1 vial
• sodium nitrite injection: 30mg/mL (300mg/10mL vial) 1 vial

Dosage Considerations – Should be Given as Follows:

Cyanide Poisoning

• Adult: Sodium nitrite: 300 mg (i.e., 10 mL) intravenously (IV) infused at rate of 2.5-5 mL/minute
• Pediatric: Sodium nitrite: 6 mg/kg (i.e., 0.2 mL/kg or 8 mL/m² BSA of 3% solution) IV infused at rate of 2.5-5 mL/minute; not to exceed 10 mL (300 mg)  
• Adult: Sodium thiosulfate: 12.5 g (50 mL of 25% solution) slow IV infusion (over 10 minutes) immediately following sodium nitrite administration; adjust infusion rate according to blood pressure
• Pediatric: Sodium thiosulfate: 250 mg/kg (ie, 1 mL/kg or 30-40 mL/m² BSA of 25% solution) slow IV infusion (over 10 minutes) immediately following sodium nitrite; adjust infusion rate according to blood pressure
• If signs of poisoning reappear, repeat treatment using one-half the original dose of both sodium nitrite and sodium thiosulfate
• Anemia: Reduce dose of sodium nitrite proportional to hemoglobin concentration

Renal Impairment

• Substantially excreted by the kidney; the risk of toxic reactions to these drugs may be greater in patients with impaired renal function

Hepatic Impairment

• Not studied

Side effects of sodium thiosulfate and sodium nitrite include:

Sodium nitrite

• Lightheadedness/fainting
• Low blood pressure (hypotension)
• Fast heart rate
• Palpitations
• Sweating
• Shortness of breath
• Abnormal heart rhythm
• Methemoglobinemia
• Headache
• Dizziness
• Rapid breathing
• Blurred vision
• Seizures
• Confusion
• Coma

Sodium thiosulfate

• Low blood pressure (hypotension)
• Headache
• Disorientation
• Nausea/vomiting
• Salty taste
• Prolonged bleeding time
• Warmth

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

• Sodium thiosulfate and sodium nitrite have no listed severe interactions with other drugs.
• Sodium thiosulfate and sodium nitrite have no listed serious interactions with other drugs.
• Sodium thiosulfate and sodium nitrite have no listed moderate interactions with other drugs.
• Sodium thiosulfate and sodium nitrite have no listed mild interactions with other drugs.
   

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

Warnings
 

This medication contains sodium thiosulfate and sodium nitrite. Do not take Nithiodote if you are allergic to sodium thiosulfate and sodium nitrite or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.

Black Box Warnings

• Sodium nitrite can cause serious adverse reactions and death from hypotension and methemoglobin formation
• Monitor to ensure adequate perfusion and oxygenation during treatment with sodium nitrite

Contraindications

• No information available

Effects of Drug Abuse

• No information available

Short-Term Effects

• See "What Are Side Effects Associated with Using Sodium Thiosulfate and Sodium Nitrite?”

Long-Term Effects

• See "What Are Side Effects Associated with Using Sodium Thiosulfate and Sodium Nitrite?”

Cautions

• Methemoglobinemia: Sodium nitrite reacts with hemoglobin to form methemoglobin and should be used with caution in patients known to have anemia
• Smoke inhalation: Carbon monoxide contained in smoke can result in the formation of carboxyhemoglobin that can reduce the oxygen-carrying capacity of the blood; sodium nitrite should be used with caution in patients with smoke inhalation injury because of the potential for worsening hypoxia due to methemoglobin formation
• Optimally, the sodium nitrite dose should be reduced in proportion to the oxygen-carrying capacity
• Use with caution if the diagnosis of cyanide poisoning is uncertain
• Coadministration with antihypertensive, phosphodiesterase-5 enzyme or diuretics should be done with caution
• Use caution in patients with anemia
• Patients with G6PD deficiency are at increased risk of hemolytic crisis
• Avoid nitrites in pregnancy due to fetal hemoglobin's susceptibility to oxidase stress

Monitoring

• Monitor patients for at least 24-48 hours after administration for adequacy of oxygenation and perfusion and recurrent signs and symptoms of cyanide toxicity
• When possible, hemoglobin/hematocrit should be obtained when treatment is initiated
• Measurements of oxygen saturation using standard pulse oximetry and calculated oxygen saturation values based on measured PO2 are unreliable in the presence of methemoglobinemia
• Methemoglobin level: Administrations of sodium nitrite solely to achieve an arbitrary level of methemoglobinemia may be unnecessary and potentially hazardous; therapeutic effects of sodium nitrite do not appear to be mediated by methemoglobin formation alone and clinical responses to sodium nitrite administration have been reported in association with methemoglobin levels less than 10%
• Administration of sodium nitrite beyond the initial dose should be guided primarily by clinical response to treatment (i.e., a second dose should be considered only if there is an inadequate clinical response to the first dose)
• Methemoglobin concentrations are closely monitored and kept below 30%; serum methemoglobin levels should be monitored during treatment using co-oximetry, and administration of sodium nitrite should generally be discontinued when methemoglobin levels exceed 30%
• Intravenous methylene blue and exchange transfusion have been reported in the literature as treatments for life-threatening methemoglobinemia

Pregnancy and Lactation

Use sodium thiosulfate and sodium nitrite with caution during pregnancy if the benefits outweigh the risks. Animal studies show risk and human studies are not available or neither animal nor human studies were done. Sodium nitrite has caused fetal death in humans as well as animals.

It is unknown whether sodium thiosulfate and sodium nitrite are distributed in breast milk. Caution is advised in breastfeeding women. Because these drugs may be administered in life-threatening situations, breastfeeding is not a contraindication to its use; there are no data to determine when breastfeeding may be safely restarted following sodium nitrite and sodium thiosulfate administration.