You can take magnesium citrate instead of magnesium sulfate ( Epsom Salts .) It's the magnesium the relaxes the bile ducts. Magnesium sulfate relaxes the ducts and is also a rather efficient laxative.
Since the citrate form doesn't have quite the same diarrhetic affect as the sulfate, the addition of a coffee enema the evening of the flush and another the morning after may help clear the bowels before releasing 'stones' and then the morning one may help clear the 'stones' out.
You don't have to do a parasite flush first to have a successful flush. It seems Clark believes that if you know you have parasites, clearing them out first will make the Liver Flushes even more productive. So many people here, myself included, have done many flushes before taking anti-parasitic herbs. In fact, some people have flushed out liver flukes without taking any parasite herbs at all!
Many times the problem people have with the anti- parasite herbs is not with the herbs but with the parasite die-off. parasites are tenacious little critters that will fight to stay in their nice warm cozy climate. If there is a large parasite infestation, quite often the digestive issues get worse before they get better. Once the little buggers have been evicted and diet changed to a more un-parasite friendly one, the digestive problems do start getting better.
Oil of oregano, Wormwood , Black-Walnut hull, pumpkin seeds, cloves, garlic, and grapefruit seed are all known to be effective against the little blighters. Some parasite programs are much more intense than others. It's easier and often cheaper to buy the herbs pre-mixed, but you can take just a couple at a time and alternate out with others every one or two weeks for a slower cleanse. Like with everything else, you need to listen to your body to see what works best for you.