NAC-- anytime. (PF POST-CYCLE also contains NAC) It seems the Tudca is more for clearing out toxins than a liver protectant, so I'd say use it after the use of orals to help restore liver function. Keep with the PF POST CYCLE because that contains picroliv and that's the only thing shown to regeneate damaged liver cells. I also like LIV 52 for detox. You can find it at good prices on amazon.