Lithium is a mood stabilizer used primarily in the treatment of bipolar disorder (depression and mania), both acutely and chronically. A preclinical study showing that lithium attenuated cannabis withdrawal in rats [79] prompted two small open-label clinical studies. In the first study, lithium (600 to 900 mg/day), administered to 9 adults for 6 days, reduced withdrawal symptoms in 4 of the 9 participants [80]. However, cannabis was admittedly smoked during this period by one of these 4 participants and cannabis abstinence was not verified in the others. In the second study, 20 cannabis-dependent participants received lithium (500 mg 2x/day) for 7 days in an inpatient detoxification facility [81]. Twelve participants completed the 7-day inpatient detoxification. Self-reported cannabis abstinence at post-treatment follow-up sessions was 64% (Day 10), 65% (Day 24), and 41% (Day 90). Participants self-reported cannabis abstinence on 88% of days post-treatment. Five participants reported continuous abstinence that was corroborated with urine toxicology tests on Day 90. These results provide limited support for a double-blind trial of lithium as treatment for cannabis dependence.
