Depends on if you are starting out with the liver or the colon. Then that depends on the condition of your liver. If you're going to be doing a colon cleanse, then I'd say wait till after the colon cleanse is done. The Zymex is taken on a empty stomach.
I didn't do the Dr. Natura colon cleanse, so I don't know how it's taken. I did the Schulze one, and with that, I was taking something every 2 hours. That might interfere with taking the Zymex.
I didn't eat very much at all when I was getting the tapeworms. That helped get them easier, I think. That was a time when I just didn't want to eat much.
Thee body only wants to do one thing at a time, so I did one thing at a time.