A typical visual aura which precedes the headache in about 20% of migraine sufferers usually lasts 20 to 60 minutes. A small number of patients suffer prolonged auras, which can last for hours. While we have many medications to treat the pain of migraine, we have no effective way to stop a prolonged aura. The only possible exception is intravenous magnesium, which I have found to help some patients for prolonged visual and other types of aura. Researchers at UCSF led by Dr. Peter Goadsby conducted a rigorous blinded study of intranasal ketamine for prolonged auras. They compared ketamine to a strong tranquilizer, midazolam. The results of the study published in Neurology showed that ketamine but not midazolam can make aura milder, but it did not shorten it. Ketamine is a drug given intravenously for anesthesia, but it has been also widely tested for the treatment of pain, albeit with mixed results.
