This week, Ira spoke with Steven Sykes, MD, a board-certified neurologist who practices general neurology and clinical neurophysiology with Cedars-Sinai Medical Group in Santa Monica, California. In this Hippocratic episode of Ira’s Everything Bagel, Dr. Sykes talks about the lesser-known cluster headache; the difference between a migraine headache and the more severe cluster headache, and observing the difference by tracking non-headache symptoms; why there are genetic factors that risk developing cluster headaches; the diagnostic testing necessary to establish the condition; acute (or rescue) treatment and preventative treatment; why oxygen at a high flow rate can be an effective treatment; some of the other treatments that are borrowed from the migraine world; the impact of prolonged cluster episodes on the personality of the patient; and what can help the doctor establish a diagnosis.