We measured the levels of the cytokines IL-1-alpha, IL-1-beta, IL-2, IL-6, TNF-alpha, and IFN-gamma in culture supernatants of stimulated whole blood cells derived from 23 tumor patients undergoing a 4-week oral treatment with a spagyric extract from Echinacea angustifolia, Eupatorium perfoliatum, and Thuja occidentalis (Echinacea complex). All patients had had curative surgery for a localized solid malignant tumor. Blood was taken before treatment and after 2 and 4 weeks of therapy. Twelve untreated tumor patients at the same clinical stage, also after curative surgery, served as a control group. In the blood cell cultures of all patients, a rather wide range of cytokine levels was found. After therapy with Echinacea complex, no significant alteration in the production of the cytokines could be seen in comparison to the controls, and also the leukocyte populations remained constant. We conclude that at this application and dosage, the therapy with Echinacea complex has no detectable effect on tumor patients' lymphocytes activity as measured by their cytokine production.