[Toxico-pharmacological study of lyophilized sodium nitroprusside (SNP)]

Sodium nitroprusside (SNP) shows a strong hypotensive activity not only in normotensive animals but also in the presence of experimentally induced arterial hypertension. Its use in intravenous perfusion produces the rapid induction of arterial hypotension lasting or only slightly exceeding the time of its administration. Most investigators consider this hypotensive activity related to the fall in peripheral resistance, as is supported by the considerable fall in diastolic blood pressure. However, an effect of SNP on heart function cannot be ruled out. After four weeks' treatment at dosages corresponding to one tenth of the LD 50, no local or general toxicity could be demonstrated.