Dear Sir, dear Madam, This afternoon, I started to feel faint from what I believe to be overheating. I felt nauseous, sleepy with a subsequent headache. Afterwards, I even developed an attack of diarrhea. I have suffered from overheating in the past so I recognize the symptoms but diarrhea didn t occur back then. That s why I would like to know whether this might be a normal symptom which will eventually dissappear or I should consult a physician.