Lithium is a naturally occurring salt that was first used for treating certain psychiatric problems. Several headache specialists recognized that it could be useful in treating cluster headaches as well. This medication acts in the brain to re-regulate hypothalamic and other brain areas related to cluster and some other headaches. It is most useful in cluster headache. Here it is used primarily to treat those who have chronic cluster headache. It may be useful in episodic cluster headache. Continue Reading