Nitrofurantoin
urinary tract infection
"This did NOT suit me

I was given 100 mg twice a day. After the first dose, suddenly Blood Pressure and pulse rate shot up in a spike. I have been having high BP and Pulse already. So took those medicines and the parameters came down to normal.

Second doze was in the night.  It didn't cause that trouble, but after sometime started getting hot flushes. However, I tolerated that. 
 
After taking the pill next day after lunch,  after say 5 minutes, heart started beating God damn fast, This time the discomfort was 3 times than the previous one. BP and Pulse were even higher. Took the pills for BP, Pulse, and double dose of tranquilizers to slowly pacify the effect. I was about to be taken to ER.

Got to discard them"