The doctor has a dream, and his dream is "to earn enough money to do exactly what he pleased: nothing" (4.340). It certainly doesn't have anything to do with helping patients, especially the ones whom he sees as "rejects" of "privileged society." You see, he really wants to be part of that privileged society, and being a poor people's doctor really emphasizes that he's not.
When Macabéa comes to see him, he doesn't show much compassion toward her. He tells her that she needs psychiatric help and that she needs to eat more—as though she's starving herself on purpose, or even knows what spaghetti is. Eventually, he gets so frustrated with her that he kicks her out of the office.
Like almost every other character in the book, he shows no genuine concern for Macabéa. He's a chubby, sweaty, cranky man who is too wrapped up in the disappointment of his own life to actually care for anybody. Macebéa leaves his office no better off than she was before she went to see him.