NOFX's Fat Mike: Thanks Allergies ... My Sex Life Is Over!!

NOFX singer Fat Mike is getting screwed ... out of getting screwed -- he just found out he's allergic to latex, and it's gonna be a big problem for his BDSM loving fiancee.

The punk icon, who's engaged to a dominatrix named Soma Snakeoil, tells TMZ his whole life changed when doctors gave him the news on the weekend. Mike says he recently started getting itchy bumps every time he and his lady "got pervy" with latex.

He says doctors told him he probably developed the allergy due to overuse.

Here's the rough part -- he can't pop a pill to treat the allergy, and the only real "cure" is to quit latex cold turkey. No easy task, considering Mike's house has a dungeon filled with latex toys.

Time to invest in lambskin?