Pop star Kesha has filed a lawsuit against her longtime producer Dr. Luke, claiming he has been abusing her since she was 18 years old. 

A lawyer for Dr. Luke has also filed a lawsuit against the singer, FOX411 has learned, claiming Kesha and her mother "are engaged in a campaign of publishing outrageous and untrue statements about Dr. Luke."

In Kesha's lawsuit, obtained by TMZ, she alleges she was sexually, physically and verbally abused by the producer for 10 years. Kesha is requesting that a judge let her out of her contract with Dr. Luke.

In the lawsuit, the singer claims Dr. Luke once made her snort a substance before she got on a plane with him and then he forced himself on her during the flight while she was drugged. She also claims he once gave her what he called “sober pills” and then she woke up in his bed the next morning with no memory of how she got there.

The suit claims the abuse was also physical and that Dr. Luke once attacked Kesha in his Malibu home, and she escaped and hid in the mountains to get away from him.

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The singer alleges the abuse led to her eating disorder, which she recently went to rehab for. The suit claims Dr. Luke told her "You are not that pretty, you are not that talented, you are just lucky to have me."

Kesha’s lawyer Mark Geragos told FOX411 in a statement, "This is just another pathetic and entirely predictable example of Dr. Luke’s continued abuse, and a misguided attempt to keep Kesha under his tyrannical control. This lawsuit has absolutely no basis in fact, the law or reality. Kesha is focused on reclaiming her voice and her freedom. She is determined to move on with her life and her career by putting this dark period behind her."

Meanwhile, Dr. Luke's lawyer insisted to us the claims made by Kesha's camp are false.

"These are allegations that Kesha and [her mother] Pebe have themselves admitted are false," Dr. Luke's lawyer told FOX411. "The complaint [filed on behalf of Dr. Luke] explains that Kesha and her mother Pebe have wielded these defamatory statements in an attempt to extort Gottwald into releasing Kesha from her exclusive recording agreement with Dr. Luke."