sodium nitrite + sodium thiosulfate at a glance
Medicine class
Cyanide antidote
Licensed use
Life-threatening acute cyanide poisoning
Administration
Slow intravenous injection by healthcare professionals
Key monitoring
Blood pressure, oxygenation and methaemoglobin
What is sodium nitrite + sodium thiosulfate used for?
The selected UK product is licensed for:
Treatment of acute cyanide poisoning judged to be life-threatening. It is an adjunct to decontamination, oxygen and cardiovascular, respiratory or seizure support—not a replacement for them.
How does sodium nitrite + sodium thiosulfate work?
Cyanide blocks cells from using oxygen. Sodium nitrite converts some haemoglobin to methaemoglobin, which attracts cyanide away from cellular enzymes. Sodium thiosulfate then supplies sulfur that helps convert cyanide into less toxic thiocyanate, which is eliminated mainly in urine.
How to take sodium nitrite + sodium thiosulfate
This is an emergency hospital treatment, not a medicine taken at home.
Both components are given by slow intravenous injection by trained healthcare professionals.
The separate sodium nitrite and sodium thiosulfate solutions are administered sequentially.
Oxygen, decontamination and other supportive measures must not be delayed.
Staff visually inspect the solutions for particles or discolouration before use.
sodium nitrite + sodium thiosulfate side effects
Common or expected effects
- Reported effects whose frequency cannot be estimated include headache, dizziness, nausea, vomiting, abdominal discomfort, warmth, sweating, weakness, a salty taste and injection-site tingling.
Get urgent medical advice
- Excessive methaemoglobinaemia, causing impaired oxygen delivery, blue or grey skin and breathlessness
- Severe low blood pressure, fainting or cardiovascular collapse
- Abnormal heart rhythm or troublesome palpitations
- Severe confusion, seizures or coma
- Urticaria or another suspected serious allergic reaction
- Haemolytic crisis, particularly in G6PD deficiency
- Prolonged bleeding time
sodium nitrite + sodium thiosulfate in pregnancy
Sodium nitrite is suspected to cause congenital malformations, while pregnancy data for sodium thiosulfate are limited. The combination should generally be avoided during pregnancy unless the woman's life-threatening clinical condition requires treatment; emergency specialists must weigh this against the dangers of cyanide poisoning.
sodium nitrite + sodium thiosulfate while breastfeeding
It is unknown whether either component passes into human milk, and risk to a breastfed child cannot be excluded. The product information states that breastfeeding should be discontinued during treatment; specialist advice is needed about subsequent feeding.
sodium nitrite + sodium thiosulfate interactions
Formal interaction studies have not been performed. Important practical considerations include:
Hydroxocobalamin
Do not administer it simultaneously through the same intravenous line because chemical incompatibility may occur.
Methaemoglobin-forming medicines, including procaine and sodium nitroprusside
They may add to sodium nitrite's effect on haemoglobin and increase the risk of impaired oxygen delivery.
Medicines that lower blood pressure
They may increase the risk or severity of hypotension, so haemodynamic monitoring is important.
Common questions about sodium nitrite + sodium thiosulfate
Answers are fully visible for fast scanning and source review.
Is sodium nitrite + sodium thiosulfate an antidote for cyanide poisoning?
Yes. The selected UK product is licensed for acute cyanide poisoning judged to be life-threatening.
Why does sodium nitrite + sodium thiosulfate contain two antidotes?
The components work differently: sodium nitrite draws cyanide away from cellular enzymes, while sodium thiosulfate helps convert it into less toxic thiocyanate.
Is sodium nitrite + sodium thiosulfate used after every possible cyanide exposure?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.