Charak Samhita
देयं त्वनिर्हृते पूर्वं पीते पश्चात् पुनः पुनः। भेषजं वमनार्थीयं प्राय आपित्तदर्शनात्॥५९॥
In case of improper emesis by the previously administered drug then the therapeutic emetic drugs are repeatedly given till the vomitus contains pitta.
english translation
deyaM tvanirhRte pUrvaM pIte pazcAt punaH punaH। bheSajaM vamanArthIyaM prAya ApittadarzanAt॥59॥
hk transliteration by Sanscript