Rectal spasing

So the only weird thing that has been happening is since I started this new medicine right when I have to poo my butt hurts really bad and my rectum spases. I've had this before when I'm herxing but it has happened everyday since I started the meds. It leaves once I go to the bathroom.

Just curious if anyone else gets this.

It would happen to me but only it would be my bladder. Every time I would try to void my bladder would spasm and I'd have to move around in different positions trying to get it to calm down and release the rest of the urine. It stopped after about a month of treatment. It's annoying. And for the record I have Bart as well.