The Compendium of Kāśyapa 8.2.41

8.2.41

tryahaṃ caturahaṃ vā'pi nātimātramataḥ param
rūkṣatvājjvaryamāṇāya deyaṃ sarpirjvarāpaham

For three days, or four days, not in excess beyond that, / clarified butter that removes fever should be given to the feverish patient on account of dryness.