Dave0423,
Thanks for the post.
This syndrome just means that you are either sensitive to your body's own adrenaline or that you make too much of it.
Beta-blockers, like labetalol, are effective therapy because they block the receptor where the adrenaline acts.
I am not aware of any adverse long-term effects of this syndrome, provided you receive adequate treatment for the high blood pressure that goes with the syndrome.
Good luck.