For cyanide poisoning

Other Uses. Other appHcations for sodium nitrite include the syntheses of saccharin [81-07-2] (see Sweeteners), synthetic caffeine [58-08-2] (22), fluoroaromatics (23), and other pharmaceuticals (qv), pesticides (qv), and organic substances as an inhibitor of polymerization (24) in the production of foam blowing agents (25) in removing H2S from natural gas (26) in textile dyeing (see Textiles) as an analytical reagent and as an antidote for cyanide poisoning (see Cyanides). 

Sodium nitrite (NaNOg) is used by emergency medical personnel as an antidote for cyanide poisoning (for this purpose, it must be administered immediately). Based on the discussion of cyanide poisoning in Section 21.10, suggest a mechanism for the life-saving effect of sodium nitrite. 

For cyanide and cyanogen, antidote should be administered as soon as possible. The Lilly Cyanide Antidote Kit contains amyl nitrite, sodium nitrite, and sodium thiosulfate. Cobalt edentate or 4-dimethylaminophenol are alternative antidotes for cyanide poisoning. Benzodiazepines or barbiturates may be required to control severe seizures. 

Nitrites may be used as an antidote for cyanide poisoning if given rapidly. They convert hemoglobin to methemoglobin, which binds cyanide in the blood before reaching the tissues. Oxygen is also given if possible. 

Why is nitrite sometimes administered as an antidote for cyanide poisoning ... 

Excessive alcohol intake can also lead to achlorhydria and it is said that the resistance for cyanide poisoning of the Russian mystic, Rasputin, was attributable to that effect. The great amount of vodka that he consumed led to achlorhydria and thus the ingested potassium cyanide did not liberate lethal hydrocyanic gas, nor was the potassium salt absorbed through the stomach walls. 

The North Atlantic Treaty Organization (NATO) and the U.S. military consider cyanide a possible weapon of so-called rogue nations such as Iraq, Iran, and North Korea, and terrorist groups. Iraq is believed to have used cyanide to kill thousands in the 1980s during its war with Iran and against Kurds in northern Iraq. With this in mind, the possibility of an antidote takes on added importance. However, the effectiveness of amyl nitrite as an antidote for cyanide poisoning has come under question by some medical authorities. The U.S. military removed amyl nitrite from its cyanide antidote kits, because of adverse side effects (low blood pressure, dizziness, and headaches) and other concerns. 

This reaction is catalyzed by rhodanase enzyme, also called mitochondrial sulfur transferase. Although not found in the blood, this enzyme does occur abundantly in liver and kidney tissue. Because of this reaction, thiosulfate can be administered as an antidote for cyanide poisoning. 

Antidotes for cyanide poisoning (B). Cyanide ions (CN ) enter the organism in the form of hydrocyanic acid (HCN) the latter can be inhaled, released from cyanide salts in the acidic stomach juice, or enzymatically liberated from bitter almonds in the gastrointestinal tract. The lethal dose of HCN can be as low as 50 mg. CN binds with high af nity to trivalent iron and thereby arrests utilization of oxygen via mitochondrial cytochrome oxidases of the respiratory chain. Internal asphyxiation (histotoxic hypoxia) ensues while erythrocytes remain charged with 02 (venous blood colored bright red). 

The only pharmacological use of vitamin B12, other than for the treatment of deficiency or for rare children with vitamin dependency diseases affecting the binding of the coenzyme to methylmalonyl CoA mutase (Section 10.8.2), is as an antidote for cyanide poisoning. Supplements of vitamin B12 are available for strict vegetarians who might be at risk of deficiency. There is no evidence of any adverse effects of high intakes of vitamin B12. 

Thankfully, the body has a detoxication system for cyanide, presumably because of the presence of naturally occurring cyanides in plants. This defence mechanism, however, can be easily overwhelmed and fatalities do occur (see p. 220). If someone working with a cyanide is found frothing a little around the mouth, an unusually brighter red colour than normal, and smelling of bitter almonds (a bit like marzipan), all is not lost, however. If they are still ahve, there is hope, for there are several antidotes and treatments for cyanide poisoning. Unfortunately, not everyone can smell cyanide as there appears to be a genetic deficiency in some people which means that they cannot detect it by its smell. 

Sodium nitrite is the most prevalent drug for cyanide poisoning. It takes about 12 min to generate approximately... 

Bhattacharya, R., Pant, S.C., Deo Kumar, Dube, S.N. (1995). Toxicity evaluation of two treatment regimens for cyanide poisoning. J. Appl. Toxicol. 15 439-41. 

Bright, J.E. (1987). A prophylaxis for cyanide poisoning. In Clinical and Experimental Toxicology of Cyanides (B. Ballantyne, T.C. Marrs, eds), pp. 359-82. lOP Publishing, Bristol, England. 

Van Heijst, A.N.P., Meredith, J.J. (1990). Antidotes for cyanide poisoning. In Basic Science in Toxicology (G.N. Volanis, J. Sims, F. Sullivan, P. Turner, eds), pp. 558-66. Taylor and Francis, Brighton, England. 

Cyanide antidote. The immediate administration of nitrite is a highly effective treatment for cyanide poisoning. What is the basis for the action of this antidote (Hint Nitrite oxidizes ferrohemoglobin to ferrihemoglobin.)... 

Or in other more bizarre ways. A 23-year-old medical student saw his dog (a puppy) suddenly collapse. He started external cardiac massage and a mouth-to-nose ventilation effort. Moments later the dog died, and the student felt nauseated, vomited and lost consciousness. On the victim s arrival at hospital, an alert medical officer detected a bitter almonds odour on his breath and administered the accepted treatment for cyanide poisoning after which he recovered. It turned out that the dog had accidentally swallowed cyanide, and the poison eliminated through the limgs had been inhaled by the master during the mouth-to-nose resuscitation. Journal of the American Medical Association 1983 249 353. 

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