I would say yes, certain things can make an existing flare even worse... For me they run the gamut from cold pills to severe stress or travel-related anxiety to certain foods... I would say that anything that can cause you to flare at all can potentially make an already existing flare worse.
At least, that's been my experience.
Also, sometimes I fall victim to that "I'm already flaring so what the crap does it matter what I eat?" and then I down a double fudge brownie sunday. Not a good idea. I always regret that, because it ALWAYS makes it worse for me.
27f, dx'd CD July '05 after 6 fistula/abscess surgeries
(miscarried at 13 weeks, now waiting to heal before trying again)
Stopped Humira August 22nd, 2008.
Went Gluten-Free, noticing some definite improvement.
Started LDN October 27th, and already LOVING IT.
"Our greatest fear is not that we are inadequate, but that we are powerful beyond measure."