In Love’s Labour’s Lost, the creation of an academe where study is posited as the antidote to the diseases of the mind caused by worldly desire results in an epidemic of lovesickness. Lovesickness, otherwise known as ‘erotic melancholy’ or ‘erotomania’, was treated in contemporary medical documents as a real, diagnosable illness, a contagious disease thought to infect the imagination through the eyes, which could be fatal if left untreated. Such representation of love as a communicable disease is drawn, I suggest, from a neoplatonic tradition led by the work of Marsilio Ficino, particularly his fifteenth-century treatise Commentary on Plato’s Symposium on Love. Ficino’s construction of eros as a kind of ‘vulgar love’, distinctive from ‘heroic love’, emphatically denotes lovesickness as a kind of material contagion with the eye as its primary means of transmission, an idea that had a more significant influence in England and on the work of playwrights like William Shakespeare than has previously been acknowledged. For all its lighthearted conceits, Love’s Labour’s Lost takes lovesickness and its etiology very seriously, in ways that have been almost entirely ignored by scholarship on this play.