i should assert that it's not necessarily the "voice of reason" that is advising one to the ER. largely, it is the voice of panic, fear, confusion, cultural acclimation, and lack of information that does it. Not always, of course, there is often a good reason to go to a doctor.
i should also assert that it is not passive to ask those who have knowlege (ie, us) for information that will serve in a timely fashion, before seeking other, more professional advice. in fact, this is pro-active, it's simply cautious and seeking out all avenues (thorough) before rushing to a busy medical professional with a non-medical problem (and thus possibly keeping said medical professional from a real emergency) that can be easily managed on one's own.
that is not to say, of course, that if one feels that a medical process is necessary and/or appropriate that they shouldn't go. it may be entirely reasonable and absolutely appropriate and proactive. but it's not always the best option, not always the "voice of reason" that dictates this behavior, and it's not the only way to be "proactive."
seeking the experience of others--and their methodologies and support--is proactive. and, others have given the advice in stages. it may solve itself--it may require herbal supplementation--it may require the administration of a professional. There is more than one option--all are reasonable, all are proactive. it simply depends upon the individual and the circumstance.
and only the individual can truly know what is right.
and that's the whole point of UC, and therefore UC support.