Increased dose of Toprol with side effects

My dr. gave me an increased dose of Toprol for my Tachycardia, but it is making me super tired & unable to do much. I feel like sleeping for a week.  Sometimes my BP is low 96/66 could this be causing the problem? should I quit taking the extra dose?
My heart rate Sun. was up to 160bpm.
Thanks,

synjyn51

[kenkeith]

Trprol may cause changes in your blood sugar levels. Also, this medicine may cover up signs of low blood sugar, such as a rapid pulse rate. Your doctor should  assess the adequacy of your medication. Appropriately a blood test known as the hemoglobin A1c may be performed to assess your blood sugar control over the past three-month period.  Kidney and liver functions should also be evaluated.

[ChatterAlly]

What dose?  have you talked to your doctor about adjusting the dose?  I had to work at different doses of Lopressor before we could find the right one for me.  I went from 100mg twice a day to 25mg 3 times, now I take 50mg 3 times a day.  A little drowsiness, but only if I don't sleep well.  That is the dose that works best for my rhythm and blood pressure.  Take care, Ally