Puzzling case. 42 yo male with h/o hypothyroidism presents with altered mental status. Complained of headache initially, then vomited several times. Completely normal vital signs. Physical exam shows he is uncooperative, but moving all extremities. Remainder of exam, including neuro, is normal. Head CT negative per radiology (and the neurosurgeon who was a family friend). WBC 13k, K 2.7. Remainder of labs negative, including TSH, alcohol and drug screen. ABG performed and I have never seen a more normal reading other than in text books. I intubated him initially just so I could do the above work-up. CXR negative. Lumbar puncture with 1 WBC, 3 RBC, normal glucose and protein, negative gram stain.