A first aspect of the invention relates to leucine, acetyl-leucine, or a pharmaceutically acceptable salt thereof, for use in treating or preventing a migraine, or one or more symptoms associated therewith. A second aspect of the invention relates to a method of treating or preventing a migraine, or one or more symptoms associated therewith, in a subject, said method comprising administering to the subject a therapeutically or prophylactically effective amount of leucine, acetyl-leucine, or a pharmaceutically acceptable salt thereof.