Pinsky filed a police report on Monday, claiming he and his family were the victims of violent threats allegedly posted on the Internet over a period of several months. During that period, a man fitting Pearson's description showed up at a radio station affiliated with Dr. Pinsky and made accusations about the doctor.
Investigators say Pinsky also received documents notifying him that he was being sued in small claims court by Pearson.
Pearson is being held on $150,000 bail.
Pinsky hosts VH1's reality show "Celebrity Rehab with Dr. Drew" and the radio show "Loveline" on Los Angeles' KROQ 106.7.