The phrase "am loose" does not have a clear antonym as it is not a specific word with a defined opposite. However, some alternatives to "am loose" could be "am tethered," "am restrained," or "am confined." These antonyms suggest being under control or limited in movement. It is important to note that the context in which "am loose" is used can impact the choice of antonym. For example, if "am loose" refers to being free from a problematic situation or obligation, antonyms could include "am tied down," "am committed," or "am obligated.