The Compendium of Kāśyapa 8.3.42

8.3.42

kevaladravyapeyatvādvikārṣī durjaraśca saḥ
pādasthito bhavet kvātho yukto'bahvagnitejasā

Because it is drunk as the pure substance, it is depleting and hard to digest. / A decoction should be reduced to a quarter, prepared with moderate fire-heat;