It’s been claimed that the overdose, which was said to have been taken on Friday (2 April), triggered a heart attack.
According to reports, the rapper, 50, was rushed to hospital, where a source says he is in a “vegetative state”.
Reports of DMX’s overdose has sent shockwaves throughout the rap community.
Among those to have sent “prayers” to the rapper, whose real name is Earl Simmons, are Ja Rule and Missy Elliott.
The former tweeted: “Prayers up for my brother DMX,” with Missy Elliott adding: “Prayers for DMX and his family.”
Rick Ross posted a video that showed him “putting [prayers} up in the sky” and hailing the rapper as “a legend”.
DMX is one of the biggest rap stars to have emerged from the 1990s.
The raper has a history of addiction and has been in and out of rehab over the years.
Most recently, he checked himself into an addiction centre in 2019, which prompted him to cancel a series of shows.
After leaving rehab, he addressed his time there during a Las Vegas show, telling fans in December 2019: “When you fall down, get back up. Everyone here has been through some s***, and you never know what God is willing to do for you until you need him to do something for you.”
In 2013, during a televised interview with American TV personality Dr Phil, DMX said that he believed he was “always going to be an addict until I die.”
Just last year, he was praised by fans after posting a bible study video during lockdown, which showed him reading passages from Ecclesiastes.