The phrase "mad about" is often used to convey passionate and intense emotions. However, there are many synonyms that can be used to express similar feelings. For instance, instead of saying "mad about," one could use synonyms such as "enamored," "smitten," or "obsessed." On the other hand, if the intensity of the emotion is more negative, other options like "furious," "irate," or "incensed" could be more appropriate. In summary, choosing the right synonym depends on the context and nature of the emotions being expressed.