RT Journal Article SR Electronic T1 Possible leukopenia associated with long-term use of echinacea. JF The Journal of the American Board of Family Practice JO J Am Board Fam Med FD American Board of Family Medicine SP 417 OP 419 VO 15 IS 5 A1 Kemp, David Eric A1 Franco, Kathleen N YR 2002 UL http://www.jabfm.org/content/15/5/417.abstract AB