Sodium Nitrite And Sodium Thiosulfate

⛔ FDA Black Box Warning

WARNING: LIFE THREATENING HYPOTENSION AND METHEMOGLOBIN FORMATION Sodium nitrite can cause serious adverse reactions and death in humans, even at doses less than twice the recommended therapeutic dose. Sodium nitrite causes hypotension and methemoglobin formation, which diminishes oxygen carrying capacity. Hypotension and methemoglobin formation can occur concurrently or separately. Because of these risks, sodium nitrite should be used to treat acute life-threatening cyanide poisoning and be used with caution in patients where the diagnosis of cyanide poisoning is uncertain . Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with sodium nitrite. Alternative therapeutic approaches should be considered in patients known to have diminished oxygen or cardiovascular reserve (e.g. smoke inhalation victims, pre-existing anemia, cardiac or respiratory compromise), and those at higher risk of developing methemoglobinemia (e.g., congenital methemoglobin reductase deficiency) as they are at greater risk for potentially life-threatening adverse events related to the use of sodium nitrite . [See Warnings and Precautions (5.1 and 5.2) ] WARNING: LIFE-THREATENING HYPOTENSION AND METHEMOGLOBIN FORMATION See full prescribing information for complete boxed warning . Sodium nitrite can cause serious adverse reactions and death from: Hypotension ( 5.1 ) Methemoglobin formation ( 5.2 ) Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with sodium nitrite.

Contraindications

4 CONTRAINDICATIONS None None. ( 4 )

Pregnancy & Breastfeeding

8.1 Pregnancy Risk Summary Life-sustaining therapy should not be withheld. Cyanide poisoning is a medical emergency in pregnancy, which can be fatal for the pregnant woman and fetus if left untreated (see Clinical Considerations ). Therefore, if a pregnant woman has known or suspected cyanide poisoning, Sodium Nitrite Injection for sequential use with Sodium Thiosulfate Injection is recommended [see Indications and Usage (1) ]. There are no available data on NITHIODOTE use in pregnant women to establish a drug-associated risk for major birth defects, miscarriage, or adverse maternal or fetal outcomes. If available, consider alternative therapies not associated with methemoglobinemia. There are no intravenous animal studies to evaluate the effect of sodium nitrite, sodium thiosulfate, or the combination on embryofetal development. In published animal studies, fetal mortality was reported when pregnant guinea pigs were subcutaneously administered sodium nitrite at 1.7 times the maximum recommended human dose (MRHD) of 450 mg sodium nitrite when maternal and fetal methemoglobin concentrations were at their peak. In other published studies, no evidence of malformations were reported in guinea pigs, mice, or rats; however, severe anemia, reduced growth, and increased pup mortality was reported when pregnant rats were treated with 4.7 times the MRHD of sodium nitrite via drinking water during gestation and throughout lactation. In published animal studies, no evidence of embryotoxicity or malformations was reported when sodium thiosulfate was administered orally during organogenesis to pregnant mice, rats, hamsters, or rabbits at 0.2 to 0.9 times the human daily dose of 12.5 g for cyanide poisoning. The sodium thiosulfate studies did not test doses that were comparable to the human dose for cyanide poisoning (see Data ). Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Cyanide readily crosses the placenta. Cyanide poisoning is a medical emergen