I had tremors and akathisia when I first started haldol back in April but I can’t take cogentin as it gives me blurry vision. So I took sinemet for awhile but it didn’t help much so I quit. Thankfully those side effects have faded mostly away. I too have tachycardia but never thought of it as a side effect of my meds as it seems to be a constant no matter what meds I’m on. I’ve never been to a cardiologist but I’ve had a few EKGs which came back normal so my dr isn’t particularly concerned.