§2.1Οὐκ ἐκκρίνει δ᾿ ἡ γαϲτὴρ ἐνίοτε καθαρτηρίου δοθέντοϲ, ἤτοι διὰ τὴν ἰδιότητα τῆϲ τοῦ κάμνοντοϲ φύϲεωϲ ἢ διὰ βραχύτητα τοῦ δοθέντοϲ φαρμάκου· πολλάκιϲ δὲ καὶ κόπροϲ ἐϲφηνωμένη ϲκληρὰ κατά τινα τῶν ἐντέρων ἐκκενωθῆναι δεομένη διὰ κλυϲτῆροϲ πρὶν δίδοϲθαι τὸ καθαῖρον φάρμακον κωλύει τὴν κένωϲιν.
And sometimes the belly does not evacuate when a purging medicine has been given, either because of the peculiarity of the patient's nature or because of the smallness of the given medicine; and often also hard feces wedged in some part of the intestines, which needed to be evacuated by means of an enema before the purging medicine was given, hinders the evacuation.
§2.2δύναται δὲ καὶ τῆϲ φύϲεωϲ. ἐπ᾿ οὖρα τὴν ὁρμὴν πεποιημένηϲ, τὸ καθαρτικὸν μηδὲν ἀνύειν.
And it is also possible, when nature has directed its impulse toward urine, that the purging medicine achieves nothing.
§2.3ἔνιά γε μήν, ὅταν ἀποτύχῃ καθαίροντα, τὰ μὲν πρὸϲ τῷ βλάπτειν μηδὲν τὸ ϲῶμα καὶ τροφὴ γίνεται τοῦ ζῴου, τὰ δ᾿ εἰϲ τὸ φάρμακόν τε καὶ δηλητήριον ἐκτρέπεται.
Indeed, some [purgatives] at least, when they fail to purge, on the one hand do not harm the body at all and even become nourishment for the living being, but on the other hand, turn into harmful drug and poison.