Charak Samhita
विरेचनं निरूहो वा तत्तीक्ष्णमिति निर्दिशेत्। जलाग्निकीटैरस्पृष्टं देशकालगुणान्वितम्॥५३॥
expulses the morbid doshas completely are said to be tikshna category of therapeutic emesis, purgation & medicated enema. The drugs which are not deteriorated by water (moisture), fire (heat & temperature), insects (microorganisms), collected from an ideal land, in specific season, with utmost required properties,
english translation
virecanaM nirUho vA tattIkSNamiti nirdizet। jalAgnikITairaspRSTaM dezakAlaguNAnvitam॥53॥
hk transliteration by Sanscript