Hits up is a verb that means to visit or contact someone, especially for a social or friendly conversation. The antonyms for this phrase depend on the context in which it is used. For instance, if hits up is used in the sense of bothering someone, the antonyms could be avoid, shun or ignore. Similarly, if the phrase is used in the sense of neglecting someone or something, the antonyms could be attend, care for or look after. Moreover, if hits up is used in the sense of giving positive feedback, praise or compliment to someone, then the antonyms could be criticize, condemn or denounce.