Cyanide tachycardia caused

Nitroprusside [nye troe PRUSS ide] is administered intravenously, and causes prompt vasodilation, with reflex tachycardia. It is capable of reducing blood pressure in all patients, regardless of the cause of hypertension. The drug has little effect outside the vascular system, acting equally on arterial and venous smooth muscle. [Note Because nitroprusside also acts on the veins, it can reduce cardiac preload.] Nitroprusside is metabolized rapidly (t1/2 of minutes) and requires continuous infusion to maintain its hypotensive action. Sodium nitroprusside exerts few adverse effects except for those of hypotension caused by overdose. Nitroprusside metabolism results in cyanide ion production, although cyanide toxicity is rare and can be effectively treated with an infusion of sodium thiosulfate to produce thiocyanate, which is less toxic and is eliminated by the kidneys (Figure 19.14). [Note Nitroprusside is poisonous if given orally because of its hydrolysis to cyanide.]... 

Dicobalt edetate. Cobalt forms stable, nontoxic complexes with cyanide. It is toxic (especially if the wrong diagnosis is made and no cyanide is present), causing hypertension, tachycardia and chest pain consequent cobalt poisoning is treated by giving sodium calcium edetate and i.v. glucose. 

Caution Very irritating and caustic produces severe dermatitis on moist skin, inhalation may cause irritation of mucous membranes. Ingestion or inhalation transitory intense redness of face, headache, vertigo, increased respirations, tachycardia, hypotension. Does not produce "cyanide" effect,... 

These changes may go unnoticed or can on occasion cause morbidity and/or mortality. From 28 January to 2 February 2005, nine cases of atypical reactions to heroin were reported from a county in New Jersey, USA. The patients had nausea, chest pain, palpitation, agitation, anxiety, tachycardia, hypotension, hyperglycemia, hypokalemia, and metabolic acidosis with increased lactate concentrations. Cyanide poisoning was suspected, but cyanide was not found and specific treatment was ineffective. However, clenbuterol was identified as an adulterant in a sample of heroin obtained by the police. A public health alert was issued usingthe USA Centers for Disease Control and Prevention s EPI-X system... 

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