We investigated the effect of a herbal formulation Okbyungpoong-Gamhmi (OG) on mast cell-dependent anaphylactic reactions by intra-rectal administration. OG concentration dependently inhibited compound 48/80-induced anaphylaxis-like response and ear swelling response with doses of 0.01-1g/kg. OG also inhibited the passive cutaneous anaphylaxis at the same concentrations. The histamine release induced by compound 48/80 or IgE from the rat peritoneal mast cells was reduced by 64.2 and 63.6%, respectively, at 1g/l. These results provide evidence that intra-rectal therapy of OG may be beneficial in the treatment of anaphylactic response.