According to TMZ, Jameson underwent a drug screening a day after partner Ortiz was arrested on Monday on felony domestic violence charges at the couple's home.
Her urine reportedly tested "negative" for ten major drugs, including cocaine, methamphetamine and oxycodone, the active ingredient in OxyContin.
Ortiz held a news conference on Tuesday claiming the domestic incident was sparked when Ortiz confronted James about her alleged addiction.
"I am definitely not addicted to OxyContin or any drug," she said.
Jameson's lawyer Ronald Richards added: "The lab tests clearly exonerate Jenna Jameson of any hint, iota, or suggestion that she ingested or was under the influence of any opiates or controlled substances."