looking for a fantasy book about bats as drugs(?)

There is a book that i checked out at the library probably at least 10 years ago that i want to find. I don't remember much but it started in a run-down desert town (i think). the main thing i remember is that the town was full of people who got high off of bats and were junkies. I think the bats may have been some aphrodisiac as well. i want to say the name of the book was dawn, dusk or something with the time of day. sorry that is barely anything to go off of...

Only one i can find dealing with bats as drugs is the post-apocalyptic novel THE PASSAGE by Justin Cronin 2010

Cronin's trilogy is one of the best in the vampire genre.