== External peer review == 

 A stroke physician I know (who once edited as ) has been so kind as to review the article. Here are his comments: 
 * IIIrd nerve best sign is complete ptosis 
 * IIIrd nerve palsy classical with posterior communicating artery 
 * Also mention about hyponatraemia with SAH due to renal Na loss and not SIADH 
 * All CT negative need LP if SAH suspected 
 * Mention exact drug regimen for Nimodipine 
 * Kick in the head doesnt really get the exact feeling = I say hit round head with a baseball bat. Thats more it 

 I must say that I haven't found a good reference for the mechanism of hyponatraemia in SAH. We don't usually do dosing regimens. I'm not sure which phrase best describes thunderclap headache; I suspect we'll be sticking with the OHCM phrasing for now.  | 