e/c/a and no products-any interference?

[powerrack]

I'm wondering if taking e/c and no products too close together could ruin the efficiancy of the no product? I've used e/c stack with regular creatine mono without thinking twice. I'm using ultimate nutrition's horsepower about 30minutes before I train and taking 25mg ephedrine and 200mg caffiene about 45minutes before I train. So far so good so I have been sticking to it.