The video also shows actor Charlie Sheen's ex-wife scoring a USD 1,500 crystal methamphetamine deal, reported Radar online.
In the video, Mueller is seen lighting and inhaling the substance which is believed to be crack cocaine. She is wearing a brown robe and her hair is unkempt.
She can be heard asking, "Where is the crystal? I am giving you USD 1500."
The video apparently was taken days before she lost custody of her twins in May.
Authorities removed her sons Max and Bob from her care earlier this year after they deemed the house unsafe for the children because of her addiction.
Mueller is fighting to regain custody of her sons. She will take random drug tests and appear in front of judge to discuss her recovery.