Cyanide poisoning antidotes

Posner MA, Rodkey FL, Tobey RE. Nitroprusside-induced cyanide poisoning Antidotal effect of hydroxocobalamin. Anesthesiology. 1976 44 330-335. 

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). 

The thiosulfate reaction with cyanide to give thiocyanate is the basis for the use of thiosulfate as an antidote in cyanide poisoning ... 

Enzymes as Antidotes. Rhodanese [9026-04-4] given along with thiosulfate to counteract cyanide poisoning in mice (224) was the first enzyme used as an antidote. This combination raised the LD q of potassium cyanide in mice by eightfold (224). 

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. 

Undoubtedly sodium nitrite is a vasodilator [1]. This is seen from anecdotal evidence when nitrite is used as an antidote to cyanide poisoning hypotension is a major hazard. However, in ex vivo experiments the effect of nitrite is small but the situation in vivo is more difficult to assess, for reasons that will be clear shortly. It is now generally assumed that nitrite acts as a vasodilator because it can undergo a spontaneous reaction to give NO. The termolecular equation (Eq. (1)) sometimes given for this process is certainly incorrect as termoleculer reactions very rarely occur. 

It must be stressed that the therapeutic value of the antidotes mentioned above is heavily dependent on the time lapse between intoxication and their use, since the usual course of inorganic cyanide poisoning is acute and proceeds at very high speeds. 

Goodhart GL. 1994. Patient treated with antidote kit and hyperbaric oxygen survives cyanide poisoning. South Med J 87(8) 814-816. 

Hume AS, Mozigo JR, McIntyre B, et al. 1995. Antidotal efficacy of alpha-ketoglutaric acid and sodium thiosulfate in cyanide poisoning. Clinical Toxicol 33(6) 721-724. 

MushettCW, Kelley KL, Boxer GE, etal. 1952. Antidotal efficacy of vitamin B12 (hydroxo-cobalamin) in experimental cyanide poisoning. Proc Soc Exp Biol Med 81 234-247. 

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. 

Acute poisoning only occurs when the detoxification mechanism is overwhelmed. This reaction is enhanced by giving sodium thiosulfate and sodium nitrate intravenously as 20% solutions in a 3 1 ratio, which is a recommended antidote for acute cyanide poisoning. It is the thiocyanate metabolite that causes chronic disease when cyanide forage is ingested over an extended period. 

Finally, it should be mentioned that HA is effective as an antidote against cyanide poisoning by virtue of converting ca 20% of the hemoglobin to methemoglobin. This will be discussed at length in Section ILF. 

Thisis due to hydrogen sulfide gas being generated in the stomach.lt is a bit unpleasant, but not dangerous. If you feel yourself developing the symptoms of cyanide poisoning, break an ampoule of amyl nitrite and inhale its contents. Seek medical attention. The foregoing does not mean that with the antidotes you can inhale fumes with impunity, only that you prob-... 

Hydroxocobalpinin (Vitamin Bu) [Vitamin/Antidote] Uses Tx of cyanide poisoning Action Binds cyanide molecules to form cyanocobal-amin to facilitate excretion Dose Adults. 5 g IV once Feds. 70 mg/kg IV once Caution [C, ] Contra Hypersensitivity to hydroxocobalamin Disp Inj SE ... 

Potassium nitrite is an antidote to cyanide poisoning. It also is a vasodilator. An important application is in the dye industry to prepare diazonium salts and azo dyes. Another use is in curing certain meat products where the salt imparts an appetizing pink color to cured meats and retards microbial growth on the meat. The commerical product is usually a nitrite-nitrate mixture, containing 85% KNO2 and 15% KNO3... 

Sodium thiosulfate is a common analytical reagent used in iodometric titration to analyze chlorine, bromine, and sulfide. Other uses are in bleaching paper pulp, bleaching straw, ivory, and bones, for removing chlorine from solutions, silver extraction from its ores, a mordant in dyeing and printing textiles, and as an antidote to cyanide poisoning. 

Cyanide poisoning poses some risk however, this is minimized both by the kinetic inertness of both Fe and Fe " cyano complexes and the high affinity of these ions for cyanide ([Fe"(CN)6] , fi6 10 [Fe "(CN)6] , Bg 10 [7, 35]. Small amounts of cyanide, which are released by photolysis and reduction products of nitroprusside, can usually be metabolized in the liver and kidneys by the enzyme rhodanase, which converts CN" to SCN [7, 36]. Cyanide can also be taken up by hydroxocobalamin to generate cy-anocobalamin (B12). As the conversion of cyanide to thiocyanate is dependent on the availability of sulfur, thiosulfate can be administered as an antidote [37]. Monitoring thiocyanate levels as an indicator of cyanide toxicity is no longer routine, but is done on patients with severe hepatic compromise who have been... 

Caution. Because of the toxic nature of cyanide, special care should be exercised in these preparations. We make amylnitrite available in the laboratory as an antidote to acute cyanide poisoning. Organic soluble salts of cyanide (and potentially cyanometallates) are especially hazardous contact poisons because they are transported intraveneously through the skin. 

Treatment of cyanide poisoning includes rapid administration of activated charcoal (although charcoal binds cyanide poorly, it can reduce absorption) and general supportive care. The conventional antidote kit available in the USA includes two forms of nitrite (amyl nitrite and sodium nitrite) and sodium thiosulfate. The nitrites induce methemoglobinemia, which binds to free CI T creating the less toxic cyanomethemoglobin thiosulfate is a cofactor in the enzymatic conversion of CN to the much less toxic thiocyanate (SCINT). Recently, the FDA approved a concentrated form of hydroxocobalamin, which is now available as the Cyanokit (EMD Pharmaceuticals, Durham, North Carolina). Hydroxocobalamin (one form of vitamin B12) combines rapidly with CN to form cyanocobalamin (another form of vitamin B12). 

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