C.I.L SUPPORT is a formulation to support the circulation (C), particularly venous system, and the (L) lymphatic drainage. The (I) stands for interstitial, which is the intercellular space (between the cells) where fluid accumulates. 
 
The herbs in this formula are termed "depuratives" an old term meaning that they aid the processes of elimination, which includes the movement of stagnant fluid in the body where metabolic by-products can accumulate. 
 
Poor venous return refers to the overwhelm of the veins and venues, often due to weak valves, causing a pooling of fluid in the intercellular space or the interstitial. A common symptom of poor venous return is heavy and uncomfortable legs.