Nitroprusside. We use nitroprusside in emergent conditions when we need to rapidly decrease peripheral vascular resistance. Although there are other options, for those acute emergent hemodynamic situations for which we need nitroprusside, there are no alternatives as controllable as nitroprusside.
Various. If you are talking ICU treatment for hypertension, IV nitroglycerin, IV hydralazine, IV ACE, sublingual clonidine, among others. In the cath lab, nitroprusside may be injected directly into the coronary artery for slow or no flow in the artery during an intervention. In that setting, adenosine or various calcium channel blockers are alternatives.