This is actually a combination of an existing beta blocker and alpha blocker that have often been used in combination as separate scrips, just put into one tablet (CoReg) to lengthen the patent protection.
It has quite a list of possible side effects, which would be expected, but the combination is supposed to have a very good effect on CHF symptoms, and acts within a half hour of the dose.
Unfortunately, while it does seem to relieve symptoms, it doesn't affect the course of the CHF. However, anything that can help in any way is worth considering.
Best wishes,