This flowering plant from the milkwort family is also known as snake root and rattlesnake root. 

Senega is used for swelling (inflammation) of the throat, nose and chest, and also for lung conditions including asthma, chronic bronchitis, and emphysema. It is also used to cause sweating, increase saliva, loosen phlegm and cleanse the bowels. Some people use Senega as a gargle for a sore throat.

The chemicals in Senega irritate the stomach lining, which causes production of larger amounts of lung secretions and act as an expectorant, Saponins are considered to be the active ingredient and are anti-inflammatory, anti-fungal and show immunopotentiating activity, which suggests they may increase specifice immune responses. 

Found in Potter’s Chest Mixture.