sodium nitroprusside (SNP), a vasodilator. ▪ INDICATIONS: It is prescribed primarily in the emergency treatment of hypertensive crises and in heart failure. ▪ CONTRAINDICATIONS: Certain compensatory forms of hypertension, such as coarctation of the aorta or impaired cerebral circulation, or known hypersensitivity to the drug prohibits its use. ▪ ADVERSE EFFECTS: Among the most serious adverse effects are a rapid fall in blood pressure or symptoms of cyanide poisoning (cyanide is produced by the metabolism of nitroprusside). Muscle spasms also may occur.
