Nipride medication is a rapidly (within seconds) and consistently acting vasodilator; has brief duration of action (2-5 min)—vascular tone can be titrated with the rate of i.v. infusion. It relaxes both resistance and capacitance vessels which reduces t.p.r. as well as c.o. (by decreasing venous return). Myocardial work is reduced—ischemia is not accentuated, as occurs with selective arteriolar dilatation). Little reflex tachycardia is produced in supine posture. Plasma renin is increased.
In patients with heart failure and ventricular dilatation, Nipride medication improves ventricular function and CO by reducing cardiac preload and afterload.
Endothelial cells, RBCs (and may be other cells) split Nipride medication to generate NO which relaxes vascular smooth muscle. The enzymes involved are different from those that produce NO from glyceryl trinitrate. Moreover, Nipride medication is nonenzymatically converted to NO (and CN) by glutathione. This may be responsible for the different pattern of vasodilator action compared to nitrates, as well as for the fact that no nitrate like tolerance develops to Nipride medication action.
Nipride medication has gained popularity in the management of hypertensive emergencies; 50 mg is added to a 500 ml bottle of saline/glucose solution. The infusion is started at 0.02 mg/mm and titrated upward with the response: 0.1—0.3 mg/minis often needed. It decomposes at alkaline pH and on exposure to light: the infusion bottle should be covered with black paper.
Nipride medication is split to release cyanide. The latter is converted in liver to thiocyanate which is excreted slowly. If larger doses are infused for more than 1-2 days, excess thiocyanate may accumulate and produce toxicity, including psychosis.
Nipride medication Side effects are mainly due to vasodilatation are— palpitation, nervousness, vomiting, perspiration, pain in abdomen, weakness, disorientation, and lactic acidosis (caused by the released cyanide).
Nipride medication has also been used to produce controlled hypotension, in refractory CHF, pump failure accompanying MI and in acute mitral regurgitation.
SONIDE, PRIJSIDE, NIPRESS 50 mg in 5 ml inj.