A 52-year old male comes to the ED with a severe headache. A triage nurse gives you his chart and says that his vital signs are normal, but he does not look well. You start to question the patient, and the following history is obtained: his headache started approximately six hours ago. He was working in his office when he started to feel squeezing-like sensation in his head. The pain has gotten worse since then, but it is still tolerable. It is independent of any physical activity or position. He already had a few similar episodes of this kind of headache in the past two years, but now the pain does not go away after aspirin as it did previously. He denies trauma as well as any associated symptoms, e.g. no visual disturbances, hearing loss, weakness, dizziness, stiff neck, loss of consciousness. He is otherwise a healthy, non-smoker, with no regular therapy or known allergies. His clinical exam is unremarkable. Conscious, GCS 15, alert and oriented, normal skin color. Blood pressure 135/82 mm Hg, pulse 78/min, 14 breaths/min, SpO2 99%, body temperature 36,4 °C. Neurologic exam shows no declines from normal, as well as the rest of the physical exam.