Robert Burton, The Anatomy of Melancholy 1.1.1:
Lycanthropia, which Avicenna calls cucubuth, others lupinam insaniam, or wolf-madness, when men run howling about graves and fields in the night, and will not be persuaded but that they are wolves, or some such beasts. Aetius and Paulus call it a kind of melancholy; but I should rather refer it to madness, as most do. Some make a doubt of it whether there be any such disease. Donat ab Altomari saith, that he saw two of them in his time: Wierus tells a story of such a one at Padua 1541, that would not believe to the contrary, but that he was a wolf. He hath another instance of a Spaniard, who thought himself a bear; Forrestus confirms as much by many examples; one amongst the rest of which he was an eyewitness, at Alcmaer in Holland, a poor husbandman that still hunted about graves, and kept in churchyards, of a pale, black, ugly, and fearful look. Such belike, or little better, were king Praetus’ daughters, that thought themselves kine. And Nebuchadnezzar in Daniel, as some interpreters hold, was only troubled with this kind of madness.
This disease perhaps gave occasion to that bold assertion of Pliny,
some men were turned into wolves in his time, and from wolves to men again: and to that fable of Pausanias, of a man that was ten years a wolf, and afterwards turned to his former shape: to Ovid’s tale of Lycaon, &c. He that is desirous to hear of this disease, or more examples, let him read Austin in his 18th book de Civitate Dei, cap. 5. Mizaldus, cent. 5. 77. Sckenkius, lib. 1. Hildesheim, spicel. 2. de Mania. Forrestus lib. 10. de morbis cerebri. Olaus Magnus, Vincentius Bellavicensis, spec. met. lib. 31. c. 122. Pierius, Bodine, Zuinger, Zeilger, Peucer, Wierus, Spranger, &c. This malady, saith Avicenna, troubleth men most in February, and is nowadays frequent in Bohemia and Hungary, according to Heurnius. Scheretzius will have it common in Livonia. They lie hid most part all day, and go abroad in the night, barking, howling, at graves and deserts;
they have usually hollow eyes, scabbed legs and thighs, very dry and pale, saith Altomarus; he gives a reason there of all the symptoms, and sets down a brief cure of them.