Researchers from Italy and the US studied changes in psychological symptoms, reasoning, abuse, tolerability, quality of life, fatigue, and ability to control movement in patients with multiple sclerosis (MS) who had never before been exposed to cannabis.

First, the details.

  • 17 patients with MS who had not been exposed to cannabis were studied over 8-weeks.
  • They were randomly divided into cannabis (cannabis plant extract; Sativex) and placebo groups. Then reversed so everybody took both treatments — crossover design.
  • Patients and researchers didn’t know the treatment given — double-blinded.
  • Each treatment lasted 3 weeks.
  • A battery of evaluative tools was used to assess the findings.

And, the results.

  • There were no significant differences in any parameter studied.
  • There was a significant positive correlation between Delta-9-tetrahydrocannabinol blood levels and scores in “interpersonal sensitivity,” “aggressive behavior,” and “paranoiac tendencies.”
  • No serious side effects, abuse tendencies, or direct withdrawal symptoms were reported.

The bottom line?
The authors concluded, “Cannabinoid treatment did not induce psychopathology and did not impair cognition [reasoning] in cannabis-naive patients with MS.”

However, higher blood levels of Delta-9-tetrahydrocannabinol (higher than used in treatment) were associated with greater interpersonal sensitivity, aggressiveness, and paranoiac features.

11/8/08 11:07 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.