Dandruff (also called Pityriasis capitis) is a seborrhoeic dermatitis of the scalp. It has been correlated with the pathological colonization of the scalp with yeast from the genus Malassezia; this illness has a worldwide distribution and represents 25% of all scalp dermatosis cases. It has been demonstrated that the extract obtained from leaves of the plant Solanum chrysotrichum possesses biological activity against dermatophytes and yeast. Different steroidal saponins with antimycotic activity have been isolated from the active extract. Clinical trials with standardized extracts prepared with this vegetal species report high rates of clinical and mycological effectiveness in the treatment of Tinea pedis,without producing secondary effects. The aim of this randomized, double blind and controlled clinical study, was to compare the therapeutic effectiveness and tolerability of a shampoo containing a standardized extract of S. chrysotrichum (applied every third day, for 4 weeks), against 2% ketoconazole in the topical treatment of Pityriasis capitis. From a total of 120 patients with the clinical diagnosis of Pityriasis capitis, 14 subjects were eliminated because the presence of Malassezia was not proved, an-other two patients withdrew from the study due to non-medical causes and one more withdrew because Tinea capitis was diagnosed. Therefore, the final analysis included 51 subjects in the experimental group and 52 in the control; in 45.6% of the cases M. furfur was identified as the pathogenic agent, in 44.66% M. globosa was isolated, and 9.71 % of the patients had a mixed infestation. At the end of the treatment period, the prepared phytopharmaceutical with the standardized extract from S. chrysotrichum achieved a clinical effectiveness (total absence of signs and symptoms produced by Pityriasis capitis) of 92.16%;the mycological effectiveness (absence of Malassezia spp. in the direct examination and culture) was 68.63 %; whilst the tolerability (absence of side effects that prompt subjects to abandon the treatment) was 100%. The therapeutic success (clinical and mycological effectiveness plus tolerability) was 64.71%. The comparison of these results with that obtained from the group treated with 2% ketoconazole, showed no significant differences (Z2, p >0.23). These results show the therapeutic effectiveness and tolerability of the standardized extract from S. chrysotrichum on the local treatment of Pityriasis capitis associated with the yeast of the genus Malassezia.