Demi Lovato is seeking treatment for drug addiction in an undisclosed rehab facility after overdosing at her home in late July. Now, the man who reportedly supplied her with the drugs is opening up about what he says happened that night.

Brandon Johnson told TMZ that Lovato texted him at 4 a.m. the morning she overdosed and asked him to come over. Johnson said they watched detective shows together and, according to TMZ, were freebasing Oxycodone. Johnson also said that it was “nothing out of the ordinary” while he hung out with Lovato. He said she fell asleep around 7 a.m. or 8 a.m. and he left.

Lovato “100 percent she knew what she was taking,” Johnson told TMZ. “I disclosed to her that these are not pharmaceutical, they’re aftermarket pills, they’re much stronger. She understood fully. It was unfortunate what happened.”

According to previous reports, an assistant found Lovato unconscious around 11:30 a.m. on the morning of July 24 and called 911. She had to be revived with Narcan, a drug that treats a narcotic overdose in an emergency situation.

“Aftermarket pills” can mean one of two things, Jamie Alan, an assistant professor of pharmacology and toxicology at Michigan State University, tells Yahoo Lifestyle. “The most likely is that they were altered or laced in some way, meaning it could be laced with fentanyl,” she says. “The second alternative is that the drug is completely synthesized off the market — they didn’t start with any ‘on the market’ pharmaceuticals and didn’t go through any sort of FDA regulation.” This is becoming more common with street drugs, particularly amphetamines, Alan says.

Johnson implied that these pills were risky, and he’s right. “When you mix fentanyl and Oxycodone [which is what reportedly happened in Lovato’s case], you’re putting two opioids together. And any time you have more than one opioid or an increase of the dose, you increase your risk of overdosing and having respiratory depression — that’s what kills you,” Alan says. There’s also “no quality control at all” with aftermarket pills, Alan points out. “There’s no testing for contaminants, dosage, or for anything,” she says. “You don’t know exactly what you’re getting and, as a result, you don’t know what the outcome is going to be.”

Read more from Yahoo Lifestyle:

• TMZ claims Demi Lovato ‘freebased’ oxycodone laced with fentanyl: What does that mean, exactly?

• ‘She could die’: Demi Lovato may leave hospital this week, but loved ones urge her to go to rehab

• Celebrities send Demi Lovato love and support after an apparent heroin overdose

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