The chief herb, fu ling, strengthens the spleen and leaches out dampness. The deputy, gan Jiang, warms the middle burner and improves the transforming power of qi, which resolves the congested fluids by addressing the root of this disorder. The combination of these two herbs, one of which increases the circulation of the fluids and the other of which warms and increases the flow of qi, is an effective method of dealing with cold due to lingering of congested fluids. Bai zhu, the assistant herb, strengthens the transformative and transportive functions of the spleen and dries dampness. The envoy, zhi gan cao, strengthens middle burner qi and harmonizes the action of other herbs.