My dad 94 years old was diagnosed with thrush 2 weeks ago, and has been given Diflucan for all this period of time. There has been no improvement in his swallowing, and he is nauseated and has thrown up. The Therapist has put him on pureed diet, which he will not eat. He had cancer on throat years ago, and radiation burned his taste buds up. The Therapist says he is having silent aspiration and is thickening everything he drinks, which he hates. Will endoscopy help rid the Thrush?