Over the weekend at the Ruff Ryders’ 20-year reunion show at Barclay’s Center in Brooklyn, DMX took the stage and apparently mumbled through his set and went on a lengthy rant in the middle of it that definitely made it sound like he was maybe on something. Now, TMZ reports that the rapper has cancelled a few upcoming tour dates that were scheduled for this week due to an “unspecified medical issue” and says that friends fear that he may have suffered a relapse with his past substance abuse issues.

UPDATE: TMZ now reports DMX checked into rehab on 4/29. “It is important right now that he take some time off to focus on his health so that he can be a better father, friend and entertainer,” the rapper’s manager Pat Gallo said in a statement.