Switching from Coreg

I was diagnosed with idiopathic dilated cardiomyopathy 4 years ago with a EF of 15%.  After about 2 years of 25 mg of coreg twice a day my EF went up to 55%.  Because the side effects (fatigue, lightheadedness, weakniess)have been so debilitating, the medication was reduced to 1/2 a few months ago.  As a result my EF is now 40% and my coreg dosage has been raised. The question I have is this.  I am thinking of switching to Toprol-XL in hopes it will be as effective as Coreg with fewer side effects.  What has been the Cleveland Clinic's experience with people taking Coreg switching to Toprol-xl to lessen side effects?  Do they maintain the EF gains they experienced taking Coreg?  I don't want to do something stupid.  However, I would like to have more stamina. Thanks, JaniceP

[CCF-M.D.-CRC]

Dear janicep,
Toprol XL (metoprolol) is another drug in the family of beta-blockers.  There is some data that it is equally effective in heart failure.  In addition it is a once-a-day drug.  However, in my experience the side-effects of beta-blockers are similar across all of the different types.  However, it may still be worth a trial.  I would discuss this with your doctor and see if he/she agrees.

[Gwells]

I have been taking heart meds for over three years. One year ago, my cardiologist switched me from coreg to toprol xl. My ef a year ago was in the 25%+ range. It took a while for me to adjust to the dizziness, etc. associated with twice a day doses of coreg, but I was really feeling pretty good at the time I changed over to Toprol. With the once a day 40 mg dose of Toprol, I felt really bad in the morning until thirty minutes or so after taking my daily Toprol xl tablet, and felt dizzy between 7-8 pm (about half way through the 24-hour Toprol time release phase). My most recent echo yielded an ef of 15%. My internist suggested that I cut my 40 mg Toprol xl tablets in half and take one half in the morning and half in the evening to alleviate the evening dizziness and morning tiredness. I have been taking half-doses twice a day for a couple of weeks and that seems to help. I am now scheduled for another test with a CHF specialist to evaluate my condition with potential to be placed on a waiting list for a heart transplant (due to my low ef and apparent declining heart strength). I plan to ask the CHF specialist to change me back, from Toprol xl to coreg.