Tu Si Zi Wan is a 11-ingredient Chinese Medicine formula with Cuscuta Seeds (Tu Si Zi), Pilose Antlers (Lu Rong), Desert-Living Cistanches (Rou Cong Rong) and Yam (Shan Yao) as principal ingredients.
Invented in 1253 AD, it belongs to the category of formulas that warm Yang and tonify.
Its main actions are: 1) warms the Kidneys and 2) prevents abnormal leakage such as urinary incontinence or seminal emissions.
In Chinese Medicine health conditions are thought to arise due to "disharmonies" in the body as a system. These disharmonies are called "patterns" and the very purpose of herbal formulas is to fight them in order to restore the body's harmony.
In this case Tu Si Zi Wan is used by TCM practitioners to fight patterns like Kidney Essence Deficiency, Kidney Qi not Firm or Kidney Yang Deficiency.
From a Western Medicine standpoint, such patterns can give rise to a range of conditions such as urinary incontinence, seminal emission or premature ejaculation for instance.