Recent News: The Deep. Natalie Farrow was recently cast on Freeform's new pilot The Deep. They are waiting to see if it get's picked up, Catch Natalie Farrow's interview, talking all things iZombie and what it was like to play Ginger.
Caffeine can increase blood pressure; long term consumption at sufficiently high doses has been associated with chronic arterial stiffness. Blood pressure increases are mediated by adenosine receptor antagonism. Caffeine can cause vasoconstriction. It is unclear if caffeine causes increased heart rate as a side effect.
Therefore, those that have the A2a gene difference could experience increased anxiety when consuming caffeine. People in an already anxious state could be prone to full-blown panic attacks if they consume caffeine during this period.