RESUMEN
Plants popularly used in Guatemala for the treatment of gonorrhoea were macerated in 50% alcohol and the tincture tested for in vitro activity against Neisseria gonorrhoeae using strains isolated from symptomatic patients and confirmed by standard bacteriological procedures. From 46 plants investigated, 13 (28.3%) showed evident inhibition zones (> 9 mm), seven (15.2%) showed small activity (6.1-8.9 mm) and 26 (56.5%) showed no activity; nine of these plants inhibited five strains of N. gonorrhoea freshly isolated. The most active plants of American origin were: bark of Bixa orellana fruits of Parmentiera edulis, leaf of Diphysa robinioides, Eupatorium odoratum, Gliricidia sepium, Physalis angulata, Piper aduncum and Prosopis juliflora, root of Casimiroa edulis, and whole Clematis dioica.