Does Different Dosage Of Losartan Cause Dizziness?

Age 61, 5 8 , 168lbs. Exercise daily. I have been on 25mg Losartan twice daily. Originally I had been on Diovan 80mg but had problems with dizzines. Thus the switch. Everything had been fine until the latest refill. The new pills are labeled 572 on one side and a D on the other. The previous pills were the size of a baby asprin. The new pills are about 3 times the size. I am now getting dizzy spells when gettin up from a chair. This started on the second day of taking the new refill. My blood pressure dropped nearly 20 points with the new refill. Could this generic have a different mix causing the problem? I will be seeing my doctor in a week.