The word Dwaya means two, Arka Dwaya means two types of swallow wort or Madar. The one which is white variety and the other is red variety. The white variety is named as Calotropis Procera and the red variety is Calotropis gigantea. Both belong to Asclepiadaceae family. In the mythologically the Arka plant is used to worship Lord Soorya the Sun God. The Arka is having Katu, Tikta Rasa, Katu Vipaka and Ushna Virya. Acharya Sushruta and Acharya Vagbhata enumerated this drug under Arkadi Gana. Acharya Bhavmishra described this drug depending upon the colour of the flower. In fact two species of the genera Calotropis are available and in each species, both white and red coloured flowers are seen which are because of eco types. But the Calotropis procera appears very rarely with white flowers. The Arka alleviates Kapha, Meda, and Visha, Krimi, Kustha. The specific action of this drug is Vrina shodhana i.e wound healing property. The present study of two types of Arka reveals the morphology, pharmacological actions, Rasa panchakas, therapeutic application, etc. according to different Ayurvedic and modern texts.