Antidotes 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 ... 

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. 

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. 

Use Diazotization (by reaction with hydrochloric acid to form nitrous acid) rubber accelerators color fixative and preservative in cured meats, meat products, fish pharmaceuticals photographic and analytical reagent dye manufacture antidote for cyanide poisoning. 

Meredith, T.J., Jacobsen, D., Haines, J.A., Berger, J.-C., and van Heijst, A.N.P., Antidotes for cyanide poisoning, Volume 2, International Program of Chemical Safety/Commission of the European Communities. Evaluation of Antidote Series, Cambridge University Press, Cambridge, CA, 1993. 

Antidotes for cyanide poisoning are effective only when administered immediately. The medical management procedures include inhalation of amyl nitrite followed by intravenous administration of about 300 mg sodium nitrite over two to four minutes and... 

I. Pharmacology. Hydroxocobalamin and cyanocobalamin are synthetic forms of vitamin B.,2 used for the treatment of pernicious anemia. Hydroxocobalamin has been recognized as an antidote for cyanide poisoning for over 40 years. Hydroxocobalamin immediately exchanges its hydroxyl group with free cyanide in the plasma to produce the nontoxic cyanocobalamin. When administered to patients with cyanide poisoning, it Improves heart rate, systolic blood pressure, and acidemia. In normal individuals, hydroxocobalamin has a plasma half-life of 3-20 hours. In patients with cyanide poisoning, the haif-life is 14-24 hours, and the complexed compound, cyanocobalamin, has a half-life of 6-12 hours. 

Ten Eyck RP, Schaerdel AD, Lynett JE, et al. 1983. Stromafree methemoglobin solution as an antidote for cyanide poisoning A preliminary study. Journal of Toxicology and Clinical Toxicology 21 343-358. 

Any antidote for cyanide poisoning must be administered quickly. One antidote is sodium thiosulfate (the hypo used in the developing of photographic film). This substance converts the cyanide ion to a thiocyanate ion that does not bind to the iron of cytochrome oxidase. 

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