Charak Samhita
छिन्नमूला विदह्यन्ते न गुल्मा यान्ति च क्षयम्। रक्तं हि व्यम्लतां याति, तच्च नास्ति न चास्ति रुक् ॥३७॥
Provoked rakta is responsible for inflammation (vidaha) which is removed by bloodletting; thus when root-cause is removed then there will be no inflammation resulting in vanishing of swelling and pain
english translation
chinnamUlA vidahyante na gulmA yAnti ca kSayam। raktaM hi vyamlatAM yAti, tacca nAsti na cAsti ruk ॥37॥
hk transliteration by Sanscript