Tincture of fresh leaves gathered at sunset just before flowering time is used to make the medicine. Common Name:  Poison Oak Causes & Symptoms for Dr. Reckeweg Rhus Toxicodendron The complaints of Rhus Toxicodendron remedy come on from exposure to cold damp weather. Allergic skin reactions, Inflammation of glands that are hot and very painful. The bruised pains often attended with numbness after stretching high up of the parts is relieved with Rhus Tox.