The flu-like nasal symptoms that result from moderate to heavy consumption of cocaine. The term arose during the 1980s when cocaine exploded upon the United States; Miami, one city of many where cocaine was particularly popular, is a place where the "common cold" rarely occurs. Thus, any person with sniffles in Miami was not sick, but instead recovering from a night or succession of nights use of cocaine. One generally does not feel the symptoms often associated with a cold--such as a fever, aches, and chills; only an extremely stuffed nasal passage.
1984 in New York City:

Robert: -sniff sniff- God damn! I think I'm coming down the Miami flu!

Simon: Well you and that lady friend of yours only did about ten to fifteen lines last night!

Robert: Hahah, I guess I deserve it then!
by Cocaine, Jane November 9, 2009
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