Tatum O'Neal has allegedly checked herself back into rehab.

The 48-year-old actress - who has previously battled against drug addiction - is reportedly said to have suffered a DRUGS relapse last month and she has voluntarily returned to a rehabilitation facility.

An insider told RadarOnline: ''Tatum made the decision to voluntarily check into rehab after having a relapse about a month ago when she began using cocaine again.''

But the source is concerned that Tatum's recovery could be hindered as she chose a rehab facility which does not follow a 12-step Alcoholics Anonymous model.

The insider added: ''Tatum is doing really, really bad at the facility she is at. Tatum isn't at a 12 step based treatment program, and that is a huge problem because someone with Tatum's addiction needs to be at a rehab facility like Betty Ford or Cirque Lodge which adhere to the 12 step model.

''Tatum is essentially in denial about how bad her addiction is. Tatum is refusing to embrace the 12 step AA model to get sober.''

Tatum's younger brother Redmond O'Neal - the son of Ryan O'Neal and late actress Farrah Fawcett - is currently in rehab in Southern California.