Hi Julesvalen, The drug furosemide is used to decrease the excess of body fluid which may be causing the rise in blood pressure or there is some sort of accumulation of fluid in the body in form of swelling and pulmonary edema. When body fluid amount is drained out from the body by using this medication, it can cause some alteration in the blood pressure. So this is normal that sometime there are some chances of change in the blood pressure. It is also common that there is fluctuation in the BP in patients of hypertension. Another important thing to know is that although furosemide can be used to control the BP in hypertension, but it is not the drug which is used for long term management of hypertension. In some cases of emergency and for few days only it is given to control BP, after that other antihypertensives are given to maintain the BP for long time. So, if you are taking this drug to maintain the BP for long time, than have a chat with your doctor to try for some other antihypertensive for long term therapy, as BP is a life long condition and require treatment. Hope this will help you.