Cat Marnell is a writer whose persona is tightly wound up with her acknowledged drug use. Last March, the book proposal for her tentatively titled memoir How to Murder Your Life, a Basketball Diaries meets The Devil Meets Prada sketch, sold to Simon & Schuster for $500,000. Earlier this week, we received a concerned tip with the subject header: "Cat Marnell almost died the other night."

According to the source, who is a friend of Marnell's, Marnell claimed she was injecting heroin at an apartment in Soho on Monday night when she stopped breathing. A friend, the source says, dragged her into the shower and gave her CPR, but she was unconscious for so long that someone called 911. An ambulance brought her to New York Presbyterian Hospital, where she stayed for roughly eight hours after receiving a dose of the opioid inhibitor Naloxone. The next day was her birthday. The source wasn't present for the episode, but says Marnell recounted the night's events to him personally the next day.

Along with Adderall, dexedrine, Vyvanse, Ritalin, Concerta, PCP, cocaine, MDMA and ecstasy, benzos, sleepings pills, painkillers, and crack, Marnell has acknowledged that she's messed around heroin ("snorted, at this point in my life at least"). But according to our source, she has told her acquaintances that she is using needles now. She reassures friends that, because she "skin-pops" like Keith Richards, she won't overdose.

Despite Monday's scare, Cat boarded a plane last night to follow Pete Doherty's band Babyshambles on tour around the UK.

We emailed Marnell, who declined to comment for the record. (Disclosure: This reporter has met Marnell socially.) We subsequently heard back from her agent, Byrd Leavell, who wrote:

Cat sent me your email. I know she is in London until the 16th and I have not heard anything about any overdoses on her end. I would say that a “concerned friend” who chooses to go to Gawker just sounds like the kind of gossip that surrounds her all the time and I would be very wary. If you run it and it is not true, we would be in a position to get our lawyers involved. Which I hate to even bring up, because it’s shitty and no one likes lawyers.

The worried friend tells us, "Hopefully others around her will wake the fuck up and realize what's at stake."

New York Presbyterian refused to confirm Marnell's stay, citing confidentiality rules. Both the New York Police Department and the New York Fired Department declined to release information about any 911 call without the patient's approval. Our source told us that Marnell claimed to have told her mother and a few others about the incident; Marnell's mother did not return our calls or emails.

[Photo via Getty Images]