I take atenolol 25 mg for fast heart rate
and while in ER, they gave me 50 mg
Lopressor (which I believe is metoprolol), one time dose of Lopressor. About a day or two later, I woke up in middle of night with elevated blood pressure and somewhat tachycardia. The blood pressure was higher than what I was used to and I attributed it to not receiving any more Lopressor. It took me about 5 days to not feel affect of Lopressor, and I only took one dose. BP hit 158/100, high for me.