As everyone said, it all depends on your body. You can try running it without an anti-e, but definitely have one on hand, same with something like cabaser for progestin just in case. a few weeks ago i ran 100mg tren.a/100mg test.p/50mg npp, ED for about 12 days, with no ancillaries( was testing a batch before production,) and i had no sides at all with the exception of my normal tren night sweats after day 4 or 5. Other people would grow tits just by looking at a bottle of deca and a bottle of tren at the same time =P So it all depends on you dude.