As If There Were No Tomorrow Meaning

(idiomatic) To an excessive degree; desperately; frantically; very quickly or very much.

Example: 1999, Carol Brightman, Sweet Chaos: The Grateful Dead's American Adventure, ISBN 9780671011178, p. 106 (Google preview):
  Starting with the Pranksters, who were the first to take LSD out of the war labs and hospitals, hippies were mixing drugs as if there were no tomorrow.