Eminem is “not very well endowed,” says his ex-wife.

Kim Mathers blasted her rapper ex-husband - whom she married twice but finally split from last year - claiming he is useless in bed and relies on sexual enhancement pills to make love.

In the scathing attack, Kim ranted: “He’s not very well endowed. If you’re going to have sex with Marshall, make sure you have a little blue pill, because otherwise it does not work.”

Kim also revealed thinking about 36-year-old Eminem - real name Marshall Mathers - makes her feel physically sick. “I can’t stand him. He’s an absolutely horrible person and he gets worse every day. I vomit in my mouth whenever I’m around him or I hear his name,” she added to Detroit radio station WKQI.

Eminem and Kim met in high school and married in 1999, before divorcing in 2001. It was later revealed Kim had attempted to commit suicide in 2000. She also sued her ex-spouse for defamation after he graphically rapped about killing her in his song “Kim.”

The couple reconciled and remarried in 2006, but had divorced again before the end of the year, though their turbulent on-and-off relationship continued.

Eminem and Kim have a 13-year-old daughter, Hailie Jade Scott, whom they share custody of.