Well then she definitely cannot even consider running for President. During the Republican primaries, the Democrats raised all kinds of questions about Michele Bachmann's fitness to be President because she once suffered from migraine headaches. If headaches are reason enough to disqualify someone as a presidential candidate, then Hillary, with her concussion, blood clot, double vision, and "lingering effects" definitely is in no condition to hold office.
If Joe Biden is fit enough, than so is Hill. Anyway, what difference does it make?/s;)