He also asked Donizetti to provide an opera for his début in Naples. Donizetti complied but the new work, "Poliuto", was banned from performance on the secular stage by the authorities because of its Christian subject matter, and Nourrit felt betrayed. Meanwhile, he had been working hard to eradicate excessive nasal resonance from his tone production, only to lose his head voice as a result. His wife, arriving in Italy in July 1838, was shocked by what she considered to be the impaired sound of his singing and by the fragile state of his physique; he was being leeched regularly and was constantly hoarse. Nonetheless, his delayed Neapolitan début, which took place in Saverio Mercadante's "Il giuramento" on 14 November 1838, proved to be a success.