The crude drug "Siberian Ginseng (SG)" has long been used in empirical Oriental medicine for the nonspecific enhancement of resistance in humans and animals. In this study, we investigated the effect of cell cultured SG by oral administration in mast cell-mediated allergic reactions. SG dose-dependently inhibited compound 48/80-induced systemic allergy with doses of 10(-2) to 1 g/kg 1 h before oral administration. Of special note, SG inhibited systemic allergy with the dose of 1 g/kg by 25%. SG (1 g/kg) also inhibited passive cutaneous allergic reaction by 51%. SG dose-dependently inhibited histamine release from rat peritoneal mast cells. When SG (0.01 mg/ml) was added, the secretion of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 in antidinitrophenyl (DNP) IgE antibody-stimulated mast cells was inhibited 39.5% and 23.3%, respectively. In addition, SG inhibited anti-DNP IgE antibody-stimulated TNF-alpha protein expression in mast cells. Our studies provide evidence that SG may be beneficial in the treatment of various types of allergic diseases.