Cramp bark is one of the most valued of all North American botanical calmatives & is especially useful for women. Chaste Tree berry is equally legendary throughout Europe, & now in the United States as well. Planetary Formulas Cramp Bark Squaw Vine Co Not for use during pregnancy. Two tablets three times daily, between meals, or as recommended by your health care professional. Take 2-3 days before menstruation, then stop taking during menstruation.