Wikipedia
Vamana ( Devanagari: वामन, IAST: Vāmana, lit. dwarf) is described in the Puranas as the fifth avatar of Vishnu, and the first incarnation of the Second Age or Treta yuga. He is the first avatar to appear as a human, although he does appear as a dwarf Brahmin.
Vamana Karma, also known as medical emesis or medical vomiting, is one of the five Pradhana Karmas of Panchakarma which is used in treating Kaphaj disorders.
Some clinical trials have used it as a treatment for depressive disorder. Some studies have shown its effectiveness for disorders of various systems of human body. It is used as a treatment for psoriasis. There are studies for its use in young prediabetics. The majority of the studies reviewed showed positive outcomes for panchakarma and allied therapies when compared to a control. Unfortunately, only a limited number of high-quality clinical trials have been conducted to date. Common limitations include low sample size, inadequate descriptions of randomization and blinding protocols, inadequate descriptions of adverse events, and nonstandard outcome measures. In spite of this, preliminary studies support the use of panchakarma and allied therapies and warrant additional large-scale research with rigorously designed trials.