“Marcellus' On Lycanthropy, or Cynanthropy. Those seized by the disease called Cynanthropy or Lycanthropy go out in the month of February for the whole night imitating wolves or dogs in all things, wandering especially around graveyards until morning. You can recognize those affected by it through the following signs: they are pale, their sight is weak, their eyes dry and they shed no tears. You should see their eyes are hollow, tongue dry, and they produce generally no saliva. They are also thirsty, and they have incurable wounds on their legs from continuous falls and the bites of dogs.
“Such are the signs of their condition. One should know that lycanthropy is a form of melancholy, which you will cure at the time of the onset of symptoms by cutting a vein and evacuating the blood until fainting and having the patient follow a diet of rich food. Let them bathe in sweet water baths, then, whey from milk having been used for three days, purge using Rufus', Archigenes' or Justin's hiera** from the gourd. After the purgings, one should use the theriac from vipers and also one should give the other things mentioned in the case of melancholia. In the evening when the disease has already come on, place on the head ointments and similar perfumes that cause sleep and rub the nostrils with opium. Sometimes also drink some hypnotics.”
*some kind of mixture of drugs
Περὶ λυκανθρωπίας ἤτοι κυνανθρωπίας Μαρκέλλου. οἱ τῇ λεγομένῃ κυνανθρωπίᾳ ἤτοι λυκανθρωπίᾳ νόσῳ κατεχόμενοι κατὰ τὸν Φευρουάριον μῆνα νυκτὸς ἐξίασι τὰ πάντα μιμούμενοι λύκους ἢ κύνας καὶ μέχρις ἡμέρας περὶ τὰ μνήματα μάλιστα διατρίβουσι. γνωρίσεις δὲ τοὺς οὕτω πάσχοντας διὰ τῶνδε· ὠχροὶ τυγχάνουσι καὶ ὁρῶσιν ἀδρανὲς καὶ ξηροὺς τοὺς ὀφθαλμοὺς ἔχουσι καὶ οὐδὲν δακρύουσι. θεάσῃ δὲ αὐτῶν καὶ κοίλους τοὺς ὀφθαλμοὺς καὶ γλῶσσαν ξηρὰν καὶ οὐδὲ ὅλως σίελον προχέουσιν. εἰσὶ δὲ καὶ διψώδεις καὶ τὰς κνήμας ἔχουσιν ἡλκωμένας ἀνιάτως διὰ τὰ συνεχῆ πτώματα καὶ τῶν κυνῶν τὰ δήγματα.
τοιαῦτα μὲν αὐτῶν τὰ γνωρίσματα· γινώσκειν δὲ χρὴ μελαγχολίας εἶδος εἶναι τὴν λυκανθρωπίαν, ἣν θεραπεύσεις κατὰ τὸν χρόνον τῆς ἐπισημασίας τέμνων φλέβα καὶ κενῶν τοῦ αἵματος ἄχρι λειποθυμίας καὶ διαιτῶν τὸν κάμνοντα ταῖς εὐχύμοις τροφαῖς. κεχρήσθω δὲ λουτροῖς γλυκέσιν, εἶτα ὀρρῷ γάλακτος χρησάμενος ἐπὶ τρεῖς ἡμέρας κάθαιρε τῇ διὰ τῆς κολυκυνθίδος ἱερᾷ Ῥούφου ἢ Ἀρχιγένους ἢ Ἰούστου, δεύτερον καὶ τρίτον παρέχων ἐκ διαστημάτων. μετὰ δὲ τὰς καθάρσεις καὶ τῇ διὰ τῶν ἐχιδνῶν θηριακῇ χρηστέον. καὶ τὰ ἄλλα παραληπτέον ὅσα ἐπὶ τῆς μελαγχολίας προείρηται. εἰς ἑσπέραν δὲ ἐπερχομένης ἤδη τῆς νόσου τοῖς ὕπνον εἰωθόσιν ἐμποιεῖν ἐπιβρέγμασι τῆς κεφαλῆς χρῆσθαι καὶ ὀσφραντοῖς τοιούτοις καὶ ὀπίῳ διαχρίειν τοὺς μυκτῆρας, ἐνίοτε δὲ καὶ ποτίζειν τινὰ τῶν ὑπνωτικῶν.
Aetius of Amida, Libri medicinales 6.11, p. 151,21–152,12 Olivieri
Not much is know about Marcellus of Side, except what is recorded in the Suda:
“Marcellus Sideta, doctor, at the time of Marcus [Aurelius] Antoninus. He wrote two forty-two medical books in epic verse, among which is also On Werewolves.”
Μάρκελλος Σιδήτης, ἰατρός, ἐπὶ Μάρκου Ἀντωνίνου. οὗτος ἔγραψε δι' ἐπῶν ἡρωϊκῶν βιβλία ἰατρικὰ δύο καὶ μ’, ἐν οἷς καὶ περὶ λυκανθρώπου.
Suda μ, entry 205