The warning - stay away from other sources of caffeine while taking this supplement. If I take my pre-workout around 5, does that mean I should not take a thermogenic or amino energy in the morning or at any other time during the day too??
That means do not take anything in conjunction. If you are taking a pre-workout upon waking and need more caffeine a few hours later, most cases are you are trying to take in way too much too soon.
Spread it out and space it at least 6-8 hours apart. If you have been taking stims for some time you need to cycle off for a good 3-4 weeks and then resume them. You will build a tolerance over time.