An?l???? ?f th? ??rr?l?t??n b?tw??n the u?? ?f eighteen v?r??u? ????h???t?v? ?ub?t?n??? shows th?t ?????n? use correlates w?th ?th?r “occasion drug?” (?u?h ?? ???t??? ?r ?m?h?t?m?n??), ?? w?ll ?? w?th h?r??n ?nd b?nz?d??z???n?? u??, ?nd ??n b? ??n??d?r?d ?? a bri