What should I discuss with my healthcare provider before receiving Nithiodote (sodium nitrite and sodium thiosulfate)?
If possible before you receive sodium nitrite and sodium thiosulfate, tell your caregivers if you have:
anemia (low red blood cells);
a genetic enzyme deficiency called glucose-6-phosphate dehydrogenase (G6PD) deficiency;
low blood pressure; or
FDA pregnancy category C. Tell your doctor if you are pregnant. It is not known whether sodium nitrite and sodium thiosulfate will harm an unborn baby. However, the benefits of treating cyanide poisoning may outweigh any risks posed by this medication, for both you and your baby.
It is not known whether this medication passes into breast milk or if it could harm a nursing baby. You should not breast-feed shortly after you have been treated with sodium nitrite and sodium thiosulfate. Ask your doctor how long you should wait before breast-feeding again. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.
In an emergency situation, it may not be possible before you are treated with sodium nitrite and sodium thiosulfate to tell your caregivers if you are pregnant or breast feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received this medication.
What other drugs will affect Nithiodote (sodium nitrite and sodium thiosulfate)?
If possible before you receive this medication, tell your doctor about all other medicines you use, especially:
blood pressure medication;
a diuretic (water pill); or
sildenafil (Viagra), tadalafil (Cialis), and other erectile dysfunction medicines.
There may be other drugs that can interact with sodium nitrite and sodium thiosulfate. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.
What are some other side effects of Nithiodote?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Bad taste in your mouth.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
If OVERDOSE is suspected
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
Warnings and Precautions
See Boxed Warning. Sodium nitrite has been associated with severe hypotension, methemoglobinemia, and death at doses less than twice recommended therapeutic doses. Hypotension may occur concurrently or separately. Sodium nitrite should be used to treat life-threatening cyanide poisoning. When the diagnosis of cyanide poisoning is uncertain and/or the patient is not in extremis, special consideration should be given to administration of sodium nitrite if the patient is known or suspected to have diminished oxygen or cardiovascular reserve (e.g., smoke inhalation victims, pre-existing anemia, substantial blood loss, cardiac or respiratory compromise) or to be at higher risk of developing methemoglobinemia (e.g., congenital methemoglobin reductase deficiency).
Supportive care alone may be sufficient treatment without administration of antidotes for many cases of cyanide intoxication, particularly in conscious patients without signs of severe toxicity. Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with sodium nitrite.
Methemoglobin levels should be monitored and oxygen administered during treatment with sodium nitrite whenever possible. When sodium nitrite is administered to humans a wide range of methemoglobin concentrations occur. Methemoglobin concentrations as high as 58% have been reported after two 300-mg doses of sodium nitrite administered to an adult. Sodium nitrite should be used with caution in the presence of other drugs that may cause methemoglobinemia such as procaine and nitroprusside. Sodium nitrite should be used with caution in patients who may be particularly susceptible to injury from vasodilation and its related hemodynamic sequelae. Hemodynamics should be monitored closely during and after administration of sodium nitrite and sodium thiosulfate, and infusion rates should be slowed if hypotension occurs.
Sodium nitrite should be used with caution in patients with known anemia. Patients with anemia will form more methemoglobin (as a percentage of total hemoglobin) than persons with normal red blood cell (RBC) volumes. Optimally, these patients should receive a sodium nitrite dose that is reduced in proportion to their oxygen carrying capacity.
Smoke Inhalation Injury
Sodium nitrite should be used with caution in persons with smoke inhalation injury or carbon monoxide poisoning because of the potential for worsening hypoxia due to methemoglobin formation.
Neonates and Infants
Neonates and infants may be more susceptible than adults and older pediatric patients to severe methemoglobinemia when sodium nitrite is administered. Reduced dosing guidelines should be followed in pediatric patients.
Because patients with G6PD deficiency are at increased risk of a hemolytic crisis with sodium nitrite administration, alternative therapeutic approaches should be considered in these patients. Patients with known or suspected G6PD deficiency should be monitored for an acute drop in hematocrit. Exchange transfusion may be needed for patients with G6PD deficiency who receive sodium nitrite.
Use with Other Drugs
Sodium nitrite should be used with caution in the presence of concomitant antihypertensive medications, diuretics or volume depletion due to diuretics, or drugs known to increase vascular nitric oxide, such as PDE5 inhibitors.
Sodium thiosulfate drug product may contain trace impurities of sodium sulfite. The presence of a trace amount of sulfites in this product should not deter administration of the drug for treatment of emergency situations, even if the patient is sulfite-sensitive.