The symptoms you have reported suggest excessive removal of fluid during dialysis
.That may be happening because you are gaining more weight in between the dialysis.
1.Start taking dialysis thrice a week if not already done.
2.Drastically reduce salt intake
3.Cut down significantly on your fluid intake say 700-800ml/day
4.Limit your weight gain in between 2 dialysis sessions to maximum 1 kg.
5.Stop taking Alkaseltzer immediately