<prompt> All are true about Sodium nitroprusside exceptIt acts on endothelium to produce Nitric OxideDrug of choice for Hypertensive emergencyIt is both arterial veno-dillatorIt can cause hypothyroidism  <response>: Sodium nitroprusside is used as a second line treatment for Hypertensive emergency DOC is Nicardipine.It is a mixed vasodilator which acts on endothelium to release Nitric oxide NO.It is metabolized by liver to produce thiocyanate and may cause hypothyroidism. 