Blue Skullcap, also known as mad dog skullcap, blue pimpernel and American skullcap, is a perennial member of the mint family that is native to North America. In contrast to many other mints, this species prefers marshes and other damp places to woodland settings or open fields. The herb was well known to Native Americans, who introduced the plant to early European settlers. Although skullcap is often used to produce tinctures and infused oils for cosmetic and other topical preparations, it is most commonly used to make teas, tonics and liquid extracts, sometimes in combination with valerian.