Charak Samhita
नाल्पं हन्त्यौषधं व्याधिं यथाऽऽपोऽल्पा महानलम् । दोषवच्चातिमात्रं स्यात्सस्यस्यात्युदकं यथा ॥३१३॥
॥ Importance of proper dosage॥ As very small quantity of water cannot extinguish big fire, similarly small doses (insufficient dose) of medicine cannot inhibit or treat disease.
english translation
nAlpaM hantyauSadhaM vyAdhiM yathA''po'lpA mahAnalam । doSavaccAtimAtraM syAtsasyasyAtyudakaM yathA ॥313॥
hk transliteration by Sanscript