It depends upon how well you get alongwith Fiber. Some people like me can feel bloated on taking more than 1 scoopful of fiber. Apart from it, i doubt if excess fiber would harm in any way.
I have gotten good results with taking fiber 20 min after Paranil. You should call up Drnatura helpline ask them the question. Alternatively you can experiment and let us all know. Have a good time detoxing.