To obtain an antiallergic and antiinflammatory agent containing a silicic acid polymer having modulating activity against a living body as an active ingredient.

This antiallergic and anti-inflammatory agent contains a silicic acid polymer obtained by polymerizing silicic acid or a silicic acid salt, having 4800-2000000 molecular weight or 75-33000 degree of polymerization as an active ingredient. The silicic acid polymer is obtained e.g. by dissolving a substance containing silicic acid such as sodium orthosilicate or sodium metasilicate or a water glass with a water soluble solvent, adjusting the solution at pH 2-10 by using an acid, and preferably drying to obtain it as a powdery form. The polymer affects nervous, immune and endocrinic systems to restore the lowering in cellular functions and useful as an antiallergic, an antiinflammatory, a peripheral blood flow improving, an abnormal perception improving or an analgesic agent, or a base agent. As a deily dosage, 1μg-10mg/kg for an adult based on the silicic acid amount is administered orally, and in the case of parenteral administration such as injection, the dosage is made (1/3)-(1/10) of the oral dosage.