bisoprolol

I would hazard a guess that this pulse rate is not connected to the increased dosage as Bisoprolol would tend to slow the pulse.  It sounds to me, though I am not an expert but a paroxysmal AFib myself) that you are experiencing an increase in the attacks.  Although this sounds depressing, remember that treated AFib is not life threatening but if you are one of the unlucky ones who have alarming symptoms you are aware of during attacks, then this is upsetting.  I wonder if your doctor has tried Flecainide which used to maintain more of a regular pulse rate for me.   GPs  would tend to increase Bisoprolol with increase of attacks.  I decided not to take it because of the side effects described by so many on this forum but the best thing is to return to your GP or consultant and tell him of your suspicions about taking this drug, and maybe work out something different for you to take.  about this drug and ask his advice on its continuation or dosage.

I think its related to coming off the higher dose. I came off Bisoprolol altogether in March from being bradycardic my heart rate was continously when awake over 100 quite often 120 when walking slow. 3 months later its slowed down and doesn't speed up too quickly.Its still needing to slow down a bit more.

As Alibalea said, you are now experiencing a withdrawal from Beta Blockers.

When people are trying to quit the drug, they go from let's say 1,25Mg to 0 Mg.

And they have the same symptoms as you: elevated heart rate while 

resting, problems with doing any physical activity, strange heart rhytms, breathing problems plus anxiety related problems.

Now, you have been taking only 1,25Mg dose for some time.

Then you have been taking 2,50 due to a mistake.

Now, your body has adjusted to a higher dose.

And now, when you returned to a lower dose, your body is now in a shock.

It works this way: imagine that your heart rate before drugs was 75.

With a 1,25Mg dose, your resting heart rate will drop to let's say 60.

With a 2,50Mg dose, your resting heart rate will drop further to let's say 50 or 55.

When your heart rate (without drugs) was 75, your heart was pumping at 100% of it's strength, pace and efficiency.

With 1,25Mg dose, your heart started to pump only at 80% (it means that a drug is trying to save your heart, but on the other hand, your heart as a muscle is more deconditioned).

When you started to take 2,50Mg dose, your heart dropped even more, from 80% of it's natural strength and efficiency to 70% of it's strength and efficiency (in pumping per minute).

So, a higher dose is slowing down your heart even more, but also, your heart as a muscle is more and more out of form or deconditioned.

Now, when you have lowered a dose from 2,50 to 1,25, your heart is suddenly forced to pump stronger (from 70% to 80%).

That is the same as being sick and lying in bed for 3 Months and then suddenly trying to run for 5 miles each day with weak muscles.

Your body will not be able to handle that, right?

Well, your heart is now forced to pump stronger and faster than on 2,50 Mg dose.

And since your heart is in a poor phyiscal condition (due to 2,50Mg dose), it will take some time until it gets back into a form and shape and until it will be again strong enough to work and pump normally at 1,25Mg dose and with 60 heart rate while resting.

In short: the higher is your dose of Beta blockers=your heart is beating slower and weaker and a drug is "protecting" a heart from beating too fast and too strong.

But, on the other hand, it also means that on higher doses, your heart is in a weaker and weaker shape (compared to your heart before drugs) since it works extremely slow all the time.

So, when you lower a dose of Beta blocker, it takes some time until your body and heart as a muscle "grow back in strength".

How long will this last?

Sometimes only 1-2 weeks, sometimes 2-3 or more Months.

Although, it will be better and better each new week.

Plus, remember, withdrawal is always hot and cold.

It means that it usually goes this way:

1. you will feel bad for 2 weeks

2. then you will have 5 good days and you will think that you are fine again

3. then suddenly, the next day, you will feel bad again (after 5 good days). But this time, a bad period will last shorter, like 4-5 days

4. then you will again have 4-5 good days

5. then 3 bad days again (but with less side effects and with a lower heart rate)

6. eventually it will be: 5 good days, 1 bad day, 7 good days, 1 bad day, 10 good days, 1 bad day etc

You will also probably experience some anxiety during this period.

About your knee replacement, I don't think that you will be fine till then, so I don't know what should you do.

Maybe you should take 2,5Mg dose a few days before the operation, and then after the operation, try to slowly go back to 1,25 this way:

Take 1 and a half dose for 2-3-4 weeks (1,25 Mg+0,62 Mg)

When you'll feel normal, lower it to 1,25 Mg dose.

Good luck